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xSpeed Cache: AI-Powered Performance Hub with MCP, Caching & CDN / 1.3.7
xSpeed Cache: AI-Powered Performance Hub with MCP, Caching & CDN v1.3.7
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← All changes | includes/class-minify-filters.php +2466 -41 1.0.9 → 1.3.7 View file →
@@ -36,8 +36,467 @@
36 36 */
37 37 private static $delay_bootstrap_printed = false;
38 38
39 39 /**
40 + * Pre-minify script URLs, keyed by handle.
41 + *
42 + * `script_loader_src` (priority 10) rewrites a local script's URL to a
43 + * hashed /cache/xspeed/min/<key>.js path long before
44 + * `script_loader_tag` (priority 20/30) runs, so the delay + exclusion
45 + * checks only ever see the hashed URL. A user targeting a script by
46 + * URL substring — the obvious thing to do, and what the UI invites —
47 + * would silently stop matching the moment minification was enabled.
48 + * Minifier::rewrite_script() records the original here so those
49 + * checks can test both. (FBS field report against 1.1.2)
50 + *
51 + * @var array<string,string>
52 + */
53 + private static $original_src = array();
54 +
55 + /**
56 + * Record a script's URL as it was BEFORE minification rewrote it.
57 + * Called from Minifier::rewrite_script().
58 + *
59 + * @param string $handle Script handle.
60 + * @param string $src Original (pre-minify) URL.
61 + */
62 + public static function remember_original_src( string $handle, string $src ): void {
63 + if ( '' !== $handle && '' !== $src ) {
64 + self::$original_src[ $handle ] = $src;
65 + }
66 + }
67 +
68 + /**
69 + * The pre-minify URL for a handle, or '' when we never rewrote it
70 + * (external script, minification off, or a handle we didn't touch).
71 + *
72 + * @param string $handle Script handle.
73 + */
74 + public static function original_src( string $handle ): string {
75 + return isset( self::$original_src[ $handle ] ) ? self::$original_src[ $handle ] : '';
76 + }
77 +
78 + /**
79 + * Reset the remembered URLs. Test-only seam.
80 + */
81 + public static function reset_original_src(): void {
82 + self::$original_src = array();
83 + }
84 +
85 + /**
86 + * Does this tag (or attribute string) opt out of optimization?
87 + *
88 + * `data-no-optimize` / `data-no-minify` are the de-facto convention
89 + * consent managers and other plugins print so optimizers keep hands
90 + * off (Borlabs Cookie stamps both on its config script). The CSS
91 + * combine buffer has honored `data-no-optimize` from the start; the
92 + * JS paths did not, so a marked consent script was still minified
93 + * into a hashed cache file — and a stale copy of a legally relevant
94 + * consent config is a correctness problem, not a cosmetic one. (#456)
95 + *
96 + * @param string $tag A full tag, or just its attribute string.
97 + */
98 + public static function tag_opts_out( string $tag ): bool {
99 + return (bool) preg_match( '#\sdata-no-(?:optimize|minify)\b#i', $tag );
100 + }
101 +
102 + /**
103 + * Pristine tags as they looked before any of our transforms, keyed by
104 + * handle. See snapshot_tag() / revert_late_marked_tag().
105 + *
106 + * @var array<string,string>
107 + */
108 + private static $pristine_tag = array();
109 +
110 + /**
111 + * Priority for the late opt-out re-check. Past Borlabs' ScriptBlocker
112 + * at 999 — the highest stamper we have seen in the wild — so the
113 + * marker has certainly landed by the time we look. (#469)
114 + */
115 + private const LATE_OPT_OUT_PRIORITY = 1000;
116 +
117 + /**
118 + * The priority the late opt-out re-check runs at.
119 + *
120 + * A site whose stamper hooks even later can move ours past it.
121 + */
122 + public static function late_opt_out_priority(): int {
123 + /**
124 + * Filter the priority of xSpeed's late data-no-optimize re-check.
125 + *
126 + * @param int $priority Default 1000.
127 + */
128 + return (int) apply_filters( 'xspeed_late_opt_out_priority', self::LATE_OPT_OUT_PRIORITY );
129 + }
130 +
131 + /**
132 + * Filter: `script_loader_tag`, priority 9 — remember the tag before we
133 + * touch it, so a marker stamped later can still be honored.
134 + *
135 + * Our three opt-out-aware transforms run at 15/20/30. A plugin that
136 + * stamps `data-no-optimize` AFTER them is invisible to all three:
137 + * Borlabs Cookie stamps at priority 100, so its consent config was
138 + * still minified into a hashed cache file AND delayed — the script
139 + * that has to run before anything else on the page ran only on first
140 + * interaction. Snapshotting here is what lets the late pass put the
141 + * original back verbatim, rather than trying to unpick each transform
142 + * in reverse. (#469)
143 + *
144 + * @param string $tag
145 + * @param string $handle
146 + * @param string $src
147 + */
148 + public static function snapshot_tag( $tag, $handle, $src ): string {
149 + if ( is_string( $tag ) && '' !== $tag && '' !== (string) $handle ) {
150 + self::$pristine_tag[ (string) $handle ] = $tag;
151 + }
152 + return (string) $tag;
153 + }
154 +
155 + /**
156 + * Filter: `script_loader_tag`, priority `LATE_OPT_OUT_PRIORITY` — hand
157 + * back the untouched tag when a late filter stamped an opt-out marker
158 + * after our transforms had already run.
159 + *
160 + * The priority has to clear the stamper, not merely the transforms:
161 + * Borlabs stamps at 100 and Borlabs' own script blocker at 999, so an
162 + * earlier hook reads a tag whose marker has not landed yet. PHP_INT_MAX
163 + * would be unfriendly to a site that legitimately wants the last word,
164 + * so this sits just past the highest stamper we know of and is
165 + * filterable. Reverting to the snapshot is deliberate: undoing
166 + * a delay rewrite in place would mean re-deriving `src` from
167 + * `data-xs-src` and stripping markers, and #273 is a standing reminder
168 + * that regex-editing these attributes in reverse goes wrong quietly.
169 + *
170 + * The pristine tag still carries whatever priority-10 filters did to
171 + * it, so only OUR changes are dropped. (#469)
172 + *
173 + * @param string $tag
174 + * @param string $handle
175 + * @param string $src
176 + */
177 + public static function revert_late_marked_tag( $tag, $handle, $src ): string {
178 + if ( ! is_string( $tag ) || '' === $tag || ! self::tag_opts_out( $tag ) ) {
179 + return (string) $tag;
180 + }
181 + $handle = (string) $handle;
182 + $pristine = isset( self::$pristine_tag[ $handle ] ) ? self::$pristine_tag[ $handle ] : '';
183 + if ( '' !== $pristine && $pristine !== $tag ) {
184 + // The marker is on the tag we were handed, not on the snapshot,
185 + // so carry it — and everything else the late filter set in the
186 + // same pass — over. A consumer reading the rendered HTML (or
187 + // our own buffer passes) must still see the opt-out it asked
188 + // for.
189 + $tag = self::copy_late_attributes( $tag, $pristine, $handle );
190 + }
191 + // The snapshot was taken on `script_loader_tag`, by which point
192 + // `script_loader_src` (priority 10) had ALREADY swapped in the
193 + // hashed cache URL — so reverting the tag alone still leaves the
194 + // minified src behind, which is the half the client actually
195 + // reported. Undo that here too, using the URL rewrite_script()
196 + // recorded. (#469)
197 + return self::restore_marked_script_src( $tag, $handle, self::current_src( $tag, (string) $src ) );
198 + }
199 +
200 + /**
201 + * The src currently on a tag, falling back to the one WordPress passed.
202 + *
203 + * After a revert the tag carries the snapshot's src, which is not
204 + * necessarily the `$src` argument this late in the chain.
205 + *
206 + * @param string $tag Tag to read.
207 + * @param string $fallback Value to use when the tag has no src.
208 + */
209 + private static function current_src( string $tag, string $fallback ): string {
210 + $open = self::open_tag_offsets( $tag );
211 + if ( null !== $open
212 + && preg_match( '#(?<![-\w])src\s*=\s*["\']([^"\']*)["\']#i', $open['attrs'], $m ) ) {
213 + return $m[1];
214 + }
215 + return $fallback;
216 + }
217 +
218 + /**
219 + * Carry the attributes a late filter added onto the snapshot tag.
220 + *
221 + * Copying only `data-no-*` would silently drop the rest of what the
222 + * stamper set in the same pass. Borlabs adds `data-cfasync="false"`
223 + * alongside its markers — the attribute that keeps Cloudflare Rocket
224 + * Loader off the consent config, i.e. the same class of breakage this
225 + * fix exists to prevent, reintroduced by the fix itself. So diff the
226 + * attribute names and bring over every one the snapshot lacks.
227 + *
228 + * Our own transform markers are excluded: they are what we are
229 + * reverting, and re-adding `data-xs-delay` would re-delay the script.
230 + *
231 + * @param string $from Tag as the late filter left it.
232 + * @param string $to Snapshot tag to stamp onto.
233 + */
234 + private static function copy_late_attributes( string $from, string $to, string $handle ): string {
235 + $late_tags = self::open_tags( $from );
236 + $to_tags = self::open_tags( $to );
237 + if ( empty( $late_tags ) || empty( $to_tags ) || count( $late_tags ) !== count( $to_tags ) ) {
238 + // Counts differ when a stamper/blocker injected or replaced a
239 + // tag inside the concatenated string, or a transform dropped an
240 + // inline block. Positional pairing is meaningless then — but
241 + // returning the bare snapshot would silently strip the opt-out,
242 + // and the buffer passes would re-optimize an unmarked tag: #469
243 + // again, on the mismatch path. Over-marking merely leaves a tag
244 + // unoptimized, so stamp the protective attributes onto every
245 + // snapshot tag instead. (#470)
246 + return self::stamp_protective_attributes( $from, $to, $to_tags );
247 + }
248 + // Pair the tags positionally and stamp each one from its own
249 + // counterpart. A stamper runs over the whole concatenated string
250 + // and may mark several of the tags in it; collapsing that onto one
251 + // tag would strip the opt-out from the others, and the buffer
252 + // passes re-test `tag_opts_out()` per tag, so an unmarked sibling
253 + // is free to be re-optimized downstream — #469 again, one pass
254 + // later. (#469)
255 + $out = $to;
256 + // Right to left: an earlier splice would shift every later offset.
257 + for ( $i = count( $to_tags ) - 1; $i >= 0; $i-- ) {
258 + $add = self::late_attribute_delta( $late_tags[ $i ]['attrs'], $to_tags[ $i ]['attrs'], $handle );
259 + if ( '' !== $add ) {
260 + $out = substr_replace( $out, $add, $to_tags[ $i ]['attrs_end'], 0 );
261 + }
262 + }
263 + return $out;
264 + }
265 +
266 + /**
267 + * Fallback when the late tag and the snapshot cannot be paired
268 + * positionally: copy only the attributes that protect the script from
269 + * optimizers — the opt-out markers plus `data-cfasync` — onto every
270 + * snapshot tag missing them. Values are taken as the stamper wrote
271 + * them on the late tag. (#470)
272 + *
273 + * @param string $from Tag as the late filter left it.
274 + * @param string $to Snapshot tag to stamp onto.
275 + * @param array $to_tags open_tags() result for $to.
276 + */
277 + private static function stamp_protective_attributes( string $from, string $to, array $to_tags ): string {
278 + $protect = array();
279 + foreach ( array( 'data-no-optimize', 'data-no-minify', 'data-cfasync' ) as $name ) {
280 + if ( preg_match(
281 + '#\s(' . preg_quote( $name, '#' ) . ')(\s*=\s*(?:"[^"]*"|\'[^\']*\'|[^\s>]*))?#i',
282 + $from,
283 + $m
284 + ) ) {
285 + $protect[ $name ] = ' ' . $name . ( isset( $m[2] ) ? $m[2] : '' );
286 + }
287 + }
288 + if ( empty( $protect ) ) {
289 + return $to;
290 + }
291 + $out = $to;
292 + // Right to left: an earlier splice would shift every later offset.
293 + for ( $i = count( $to_tags ) - 1; $i >= 0; $i-- ) {
294 + $add = '';
295 + foreach ( $protect as $name => $attr ) {
296 + if ( ! preg_match( '#\s' . preg_quote( $name, '#' ) . '\b#i', $to_tags[ $i ]['attrs'] ) ) {
297 + $add .= $attr;
298 + }
299 + }
300 + if ( '' !== $add ) {
301 + $out = substr_replace( $out, $add, $to_tags[ $i ]['attrs_end'], 0 );
302 + }
303 + }
304 + return $out;
305 + }
306 +
307 + /**
308 + * The attributes present on the late tag but not the snapshot, minus
309 + * the ones OUR transforms put there for this handle.
310 + *
311 + * Only attributes recorded in $our_late_attrs are dropped — a blanket
312 + * defer/type skip threw away a defer the STAMPER set in the same pass
313 + * as its marker. Themify prints main.js with defer + data-no-optimize
314 + * together, and its config rides a deferred data: URI script printed
315 + * just before it; stripping the theme's defer made main.js
316 + * parser-blocking, so it ran ahead of its config and the theme died
317 + * with "themify_vars is not defined". `src` is still never copied:
318 + * it belongs to the snapshot, and restore_marked_script_src() owns
319 + * undoing a minified URL.
320 + *
321 + * @param string $late_attrs Attribute string from the transformed tag.
322 + * @param string $to_attrs Attribute string from the snapshot tag.
323 + * @param string $handle Script handle the tags belong to.
324 + */
325 + private static function late_attribute_delta( string $late_attrs, string $to_attrs, string $handle ): string {
326 + $pattern = '#\s([-\w:]+)(?:\s*=\s*(?:"[^"]*"|\'[^\']*\'|[^\s>]*))?#';
327 + if ( ! preg_match_all( $pattern, $late_attrs, $late, PREG_SET_ORDER ) ) {
328 + return '';
329 + }
330 + $have = array();
331 + if ( preg_match_all( $pattern, $to_attrs, $existing, PREG_SET_ORDER ) ) {
332 + foreach ( $existing as $attr ) {
333 + $have[ strtolower( $attr[1] ) ] = true;
334 + }
335 + }
336 + $add = '';
337 + foreach ( $late as $attr ) {
338 + $name = strtolower( $attr[1] );
339 + if ( isset( $have[ $name ] ) || 'src' === $name || isset( self::$our_late_attrs[ $handle ][ $name ] ) ) {
340 + continue;
341 + }
342 + if ( 0 === strpos( $name, 'data-xs-' ) ) {
343 + continue;
344 + }
345 + $add .= $attr[0];
346 + }
347 + return $add;
348 + }
349 +
350 + /**
351 + * Attribute names OUR transforms added in this request, keyed by
352 + * handle: defer_script_tag() records `defer`, delay_script_tag()
353 + * records `type` when it parks an inline block. Copying one of these
354 + * from the late tag back onto the snapshot would re-apply the very
355 + * transform the revert is undoing — but the same names coming from a
356 + * STAMPER are the author's intent and must survive, so the skip is
357 + * per-handle, never by name alone. `data-xs-*` is handled by prefix
358 + * separately. (#469)
359 + *
360 + * @var array<string,array<string,true>>
361 + */
362 + private static $our_late_attrs = array();
363 +
364 + /**
365 + * Locate the opening `<script>` that carries the src, falling back to
366 + * the last one when none does.
367 + *
368 + * WP_Scripts::do_item() hands `script_loader_tag` the concatenation of
369 + * before_inline + external + after_inline, so the FIRST `<script` is
370 + * routinely an inline block rather than the asset — the same trap
371 + * #234 fixed for defer and #273 for delay. Scanning attribute-wise
372 + * also means a quoted value containing `>` (an `onerror` guard, a JSON
373 + * payload) cannot truncate the tag the way `[^>]*` did. (#469)
374 + *
375 + * @param string $tag Full tag string.
376 + * @return array{attrs:string,attrs_end:int}|null
377 + */
378 + private static function open_tag_offsets( string $tag ): ?array {
379 + $tags = self::open_tags( $tag );
380 + $fallback = null;
381 + foreach ( $tags as $found ) {
382 + if ( preg_match( '#(?<![-\w])src\s*=#i', $found['attrs'] ) ) {
383 + return $found;
384 + }
385 + $fallback = $found;
386 + }
387 + return $fallback;
388 + }
389 +
390 + /**
391 + * Every well-formed opening `<script>` in the string, in order.
392 + *
393 + * @param string $tag Full tag string.
394 + * @return array<int,array{attrs:string,attrs_end:int}>
395 + */
396 + private static function open_tags( string $tag ): array {
397 + if ( ! preg_match_all( '#<script\b#i', $tag, $m, PREG_OFFSET_CAPTURE ) ) {
398 + return array();
399 + }
400 + $found = array();
401 + foreach ( $m[0] as $hit ) {
402 + $start = (int) $hit[1] + strlen( $hit[0] );
403 + $end = self::scan_open_tag_end( $tag, $start );
404 + if ( null === $end ) {
405 + continue;
406 + }
407 + $found[] = array(
408 + 'attrs' => substr( $tag, $start, $end - $start ),
409 + 'attrs_end' => $end,
410 + );
411 + }
412 + return $found;
413 + }
414 +
415 + /**
416 + * Offset of the `>` closing an opening tag, skipping any that sit
417 + * inside a quoted attribute value. Null when the tag is unterminated.
418 + *
419 + * @param string $tag Full tag string.
420 + * @param int $offset Index just past `<script`.
421 + */
422 + private static function scan_open_tag_end( string $tag, int $offset ): ?int {
423 + $len = strlen( $tag );
424 + $quote = '';
425 + for ( $i = $offset; $i < $len; $i++ ) {
426 + $char = $tag[ $i ];
427 + if ( '' !== $quote ) {
428 + if ( $char === $quote ) {
429 + $quote = '';
430 + }
431 + continue;
432 + }
433 + if ( '"' === $char || "'" === $char ) {
434 + $quote = $char;
435 + continue;
436 + }
437 + if ( '>' === $char ) {
438 + // A self-closing `/>` keeps the slash out of the attributes.
439 + return ( $i > $offset && '/' === $tag[ $i - 1 ] ) ? $i - 1 : $i;
440 + }
441 + }
442 + return null;
443 + }
444 +
445 + /**
446 + * Filter: `script_loader_tag`, priority 15 — undo the minify-cache
447 + * rewrite for a script whose printed tag opts out.
448 + *
449 + * The src rewrite happens on `script_loader_src` (priority 10), long
450 + * before any plugin's own `script_loader_tag` filter can stamp
451 + * `data-no-minify` onto the tag — so the marker arrived too late to
452 + * prevent the rewrite. This runs after the filters that stamp at the
453 + * default priority 10 and swaps the hashed cache URL back to the
454 + * recorded original. A marker stamped later than our transforms is
455 + * caught by revert_late_marked_tag() in the late pass instead. (#469)
456 + *
457 + * @param string $tag
458 + * @param string $handle
459 + * @param string $src
460 + */
461 + public static function restore_marked_script_src( $tag, $handle, $src ): string {
462 + if ( ! is_string( $tag ) || '' === $tag || ! self::tag_opts_out( $tag ) ) {
463 + return (string) $tag;
464 + }
465 + $original = self::original_src( (string) $handle );
466 + if ( '' === $original || '' === (string) $src || false === strpos( $tag, (string) $src ) ) {
467 + return $tag;
468 + }
469 + return str_replace( (string) $src, $original, $tag );
470 + }
471 +
472 + /**
473 + * Does a user-supplied target match this script?
474 + *
475 + * A target is either a script handle (exact) or a URL substring. The
476 + * URL is checked against BOTH the current src and the pre-minify src,
477 + * so a target written against the real asset path keeps working once
478 + * minification starts rewriting URLs to hashed cache paths.
479 + *
480 + * @param string $needle Target from the user's list.
481 + * @param string $handle Script handle.
482 + * @param string $src Current (possibly rewritten) src.
483 + */
484 + private static function target_matches( string $needle, string $handle, string $src ): bool {
485 + if ( '' === $needle ) {
486 + return false;
487 + }
488 + if ( $handle === $needle ) {
489 + return true;
490 + }
491 + if ( '' !== $src && false !== stripos( $src, $needle ) ) {
492 + return true;
493 + }
494 + $original = self::original_src( $handle );
495 + return '' !== $original && false !== stripos( $original, $needle );
496 + }
497 +
498 + /**
40 499 * Filter: `script_loader_tag` — add defer="defer" to non-excluded
41 500 * scripts. WordPress passes the full <script> tag string, the
42 501 * handle, and the src. We bail when:
43 502 * - the user excluded this handle / src substring,
@@ -60,8 +519,12 @@
60 519 // bundle's <script> tag intact so the dashboard mounts.
61 520 if ( self::skip_in_non_frontend_context() ) {
62 521 return $tag;
63 522 }
523 + // The author asked every optimizer to leave this tag alone.
524 + if ( self::carries_optimizer_opt_out( $tag ) ) {
525 + return $tag;
526 + }
64 527 if ( '' === (string) $src ) {
65 528 return $tag;
66 529 }
67 530 if ( self::is_excluded_script( (string) $handle, (string) $src ) ) {
@@ -66,12 +529,44 @@
66 529 }
67 530 if ( self::is_excluded_script( (string) $handle, (string) $src ) ) {
68 531 return $tag;
69 532 }
533 + // The tag itself asked to be left alone. (#456)
534 + if ( self::tag_opts_out( $tag ) ) {
535 + return $tag;
536 + }
537 + // Inline code elsewhere on the page reads this handle (or something
538 + // it depends on). Inline blocks never defer, so deferring this one
539 + // would run the consumer first. Defer only — delay is an opt-in
540 + // target list, where the user has named the script deliberately.
541 + if ( isset( self::inline_bound_handles()[ (string) $handle ] ) ) {
542 + return $tag;
543 + }
544 + // NB: is_protected_from_bundling() is the same two rules in one call
545 + // for the combiner; the split here is deliberate, since the
546 + // exclusion check above already ran and short-circuits earlier.
70 547 if ( false !== stripos( $tag, ' defer' ) || false !== stripos( $tag, ' async' ) ) {
71 548 return $tag;
72 549 }
73 - return (string) preg_replace( '#<script\b#i', '<script defer="defer"', $tag, 1 );
550 + // Target the <script> that actually carries a src, NOT simply the
551 + // first one in the string. WP_Scripts::do_item() hands this filter
552 + // the CONCATENATION of before_inline + external + after_inline, so
553 + // for any handle carrying a `before` inline script the first
554 + // `<script` is the inline block. Deferring that is a no-op (the HTML
555 + // spec ignores defer on inline scripts) AND leaves the external
556 + // script undeferred while its dependencies get deferred — which
557 + // inverts WordPress's guaranteed execution order and throws in any
558 + // dependent that touches a global its dependency defines. (#234)
559 + //
560 + // The lookahead scans only within the tag (`[^>]*`) for ` src=`, so
561 + // an inline `<script id="…-js-before">` can never match.
562 + $deferred = (string) preg_replace( '#<script\b(?=[^>]*\ssrc\s*=)#i', '<script defer="defer"', $tag, 1 );
563 + if ( $deferred !== $tag ) {
564 + // Remember that THIS defer is ours, so the late opt-out revert
565 + // drops it — and only it, never a stamper's own defer.
566 + self::$our_late_attrs[ (string) $handle ]['defer'] = true;
567 + }
568 + return $deferred;
74 569 }
75 570
76 571 /**
77 572 * Filter: `script_loader_tag` — rewrite src= to data-xs-src= so the
@@ -90,31 +585,624 @@
90 585 }
91 586 if ( self::skip_in_non_frontend_context() ) {
92 587 return $tag;
93 588 }
94 - if ( self::is_excluded_script( (string) $handle, (string) $src ) ) {
589 + // The author asked every optimizer to leave this tag alone.
590 + if ( self::carries_optimizer_opt_out( $tag ) ) {
95 591 return $tag;
96 592 }
593 + if ( self::is_excluded_script( (string) $handle, (string) $src, true ) ) {
594 + return $tag;
595 + }
596 + // The tag itself asked to be left alone. (#456)
597 + if ( self::tag_opts_out( $tag ) ) {
598 + return $tag;
599 + }
600 + if ( ! self::is_delay_target( (string) $handle, (string) $src ) ) {
601 + return $tag;
602 + }
603 + // Inline code elsewhere on the page reads this handle (or something
604 + // it depends on) — same registry walk defer uses. Delaying it runs
605 + // the consumer at parse time against a global that arrives on first
606 + // interaction: `wp_add_inline_script( 'jquery-ui-core',
607 + // 'jQuery.uiBackCompat…', 'before' )` throws "jQuery is not defined"
608 + // the moment jquery-core is delayed. A handle the user NAMED in
609 + // delay_js_targets is still delayed — an explicit entry is the user
610 + // saying they know the inline consumer is safe to break or absent.
611 + if ( isset( self::inline_bound_handles()[ (string) $handle ] )
612 + && ! self::is_user_named_target( (string) $handle, (string) $src )
613 + // Smart Delay inverts this protection: the handle is delayed and
614 + // its own before/after snippets are parked WITH it (see
615 + // park_smart_inline()), so the consumer no longer runs against a
616 + // missing global — it replays after its provider, in page order.
617 + // On a builder page nearly every script is inline-bound, which is
618 + // why delay-all without this delayed almost nothing.
619 + && ! self::smart_delay_enabled() ) {
620 + return $tag;
621 + }
622 + // A non-executable type means this tag is data, or is being held by
623 + // somebody else on purpose. The buffer pass has always checked this;
624 + // the enqueue path did not, so a consent-blocked or JSON-carrying
625 + // handle could still be rewritten here. (#274)
626 + if ( in_array( self::extract_type( $tag ), self::NON_EXECUTABLE_TYPES, true ) ) {
627 + return $tag;
628 + }
97 629 // src= variant: swap src → data-xs-src and add data-xs-delay marker.
98 630 if ( '' !== (string) $src ) {
631 + // Anchor on the opening <script …> tag that carries the src.
632 + // Matching a bare `src=` across the whole string would rewrite
633 + // the first occurrence anywhere — including inside a `before`
634 + // inline block, where JS like `el.src = "…"` becomes the
635 + // syntax error `el.data-xs-src="…" data-xs-delay="1"` and the
636 + // real external script is left undelayed. $tag is the
637 + // concatenation of before_inline + external + after_inline,
638 + // so that is a routine shape, not a corner case. (#234)
639 + // `(?<![-\w])` where `\b` used to be. A hyphen is a non-word
640 + // character, so `\bsrc=` also matches the TAIL of any
641 + // `data-…-src=` attribute — and consent managers and other
642 + // optimizers park a blocked script's real URL in exactly that
643 + // shape. Complianz's `data-cmplz-src` became
644 + // `data-cmplz-data-xs-src`, so after the visitor clicked Accept
645 + // the plugin looked for an attribute that no longer existed and
646 + // the script never loaded: analytics and pixels silently dead,
647 + // no console error, nothing in the UI. Same class of bug as the
648 + // image-dimension resolver in #328. (#273)
99 649 return (string) preg_replace(
100 - '#\bsrc\s*=\s*(["\'][^"\']*["\'])#i',
101 - 'data-xs-src=$1 data-xs-delay="1"',
650 + '#(<script\b[^>]*?)(?<![-\w])src\s*=\s*(["\'][^"\']*["\'])#i',
651 + '$1data-xs-src=$2 data-xs-delay="1"',
102 652 $tag,
103 653 1
104 654 );
105 655 }
106 - // Inline script: change type to text/plain so the browser
107 - // doesn't execute, mark for bootstrap rewriter.
108 - return (string) preg_replace(
656 + // Inline script: change type to text/xspeed-delayed so the browser
657 + // doesn't execute, mark for bootstrap rewriter. Any existing type
658 + // is REPLACED, not appended-after: HTML keeps an attribute's first
659 + // occurrence, so a snippet carrying its own `type="text/javascript"`
660 + // would win over a marker appended behind it and keep executing.
661 + // A non-default original type is stashed in data-xs-type so the
662 + // bootstrap can restore it on replay (#274 — type is what a script
663 + // IS; a parked `type="module"` must come back as a module).
664 + $parked = (string) preg_replace_callback(
109 665 '#<script\b([^>]*)>#i',
110 - '<script$1 type="text/xspeed-delayed" data-xs-delay="1">',
666 + static function ( array $m ): string {
667 + return '<script' . self::park_type_attrs( $m[1] ) . '>';
668 + },
111 669 $tag,
112 670 1
113 671 );
672 + if ( $parked !== $tag ) {
673 + // The parked type is ours to drop on a late opt-out revert; an
674 + // author-set type sits on the snapshot and survives regardless.
675 + self::$our_late_attrs[ (string) $handle ]['type'] = true;
676 + }
677 + return $parked;
114 678 }
115 679
116 680 /**
681 + * Script types the buffer pass must never touch. `<script>` carries
682 + * data as often as it carries code: JSON-LD feeds structured-data
683 + * consumers, importmaps must resolve before any module runs, and our
684 + * own delayed-inline marker is already handled by the bootstrap.
685 + * Rewriting any of these breaks the page or its metadata.
686 + */
687 + /**
688 + * Attributes by which a script's own author tells optimizers to stand down.
689 + *
690 + * The report behind #275 also asked us to leave a script alone when its
691 + * author "already marked it to load late". Read literally that means
692 + * `defer`/`async`, and that reading is wrong twice over: `defer` is
693 + * stamped onto every enqueued script by our OWN Defer JS filter at
694 + * priority 20, before Delay JS sees it at 30 — so honouring it would
695 + * switch Delay JS off entirely on sites running both — and `async` is the
696 + * shape of gtag, GTM and every pixel loader, which is precisely the
697 + * payload Delay JS exists to postpone. `defer`/`async` say WHEN TO FETCH,
698 + * not "leave me alone".
699 + *
700 + * These attributes do say it. Each is an established opt-out honoured by
701 + * another optimizer — WP Rocket, LiteSpeed, Autoptimize, NitroPack,
702 + * Jetpack Boost — so an author who prints one has already declared that
703 + * no optimizer should touch this tag. Consent banners are the main
704 + * beneficiary, but the rule is general and needs neither a handle nor a
705 + * recognised URL, so it works identically on both passes.
706 + *
707 + * Two deliberate omissions:
708 + *
709 + * - `data-cfasync="false"` is a Cloudflare Rocket Loader opt-out, and
710 + * ad stacks (Mediavine, Ezoic, AdThrive) print it on exactly the
711 + * heavy loaders a site turns Delay JS on for. Honouring it would
712 + * un-delay the ads.
713 + * - `data-no-minify` is about minification, not execution timing.
714 + */
715 + private const OPT_OUT_ATTRIBUTES = array(
716 + 'nowprocket', // WP Rocket
717 + 'data-nowprocket', // WP Rocket
718 + 'data-no-optimize', // LiteSpeed
719 + 'data-noptimize', // Autoptimize
720 + 'data-no-defer', // used by several optimizers
721 + 'nitro-exclude', // NitroPack
722 + 'data-jetpack-boost', // Jetpack Boost (value "ignore")
723 + 'data-wpmeteor-nooptimize', // WP Meteor
724 + 'data-xs-nodelay', // ours
725 + );
726 +
727 + /**
728 + * Does this tag carry an explicit "optimizers keep out" attribute?
729 + *
730 + * Same `(?<![-\w])` lookbehind the rest of this file uses, so
731 + * `data-nowprocket` does not also satisfy a bare `nowprocket` lookup, and
732 + * a trailing `\b` so `data-no-defer` does not match `data-no-deferral`.
733 + * Bare and valued forms both count: an author writes `nowprocket`,
734 + * `nowprocket=""` and `data-noptimize="1"` interchangeably.
735 + *
736 + * @param string $tag Full opening tag.
737 + */
738 + private static function carries_optimizer_opt_out( string $tag ): bool {
739 + // Read ATTRIBUTE NAMES, not the tag as a string. A substring scan
740 + // matched `src="https://cdn/nowprocket/loader.js"`, `?nowprocket=1`,
741 + // `class="nowprocket"` and any inline body that merely mentioned one
742 + // of these names -- each silently un-delaying a script that should
743 + // have been delayed.
744 + //
745 + // EVERY opening tag is checked, not just the first. On the enqueue
746 + // path WP_Scripts::do_item() hands us translations + before-inline +
747 + // the real tag + after-inline concatenated, so the first `<script`
748 + // is often an inline block and the author's opt-out sits on the
749 + // external tag behind it. Reading only the first tag missed it and
750 + // delayed the script anyway -- the wrong direction: a consent banner
751 + // its author told optimizers to leave alone would not appear.
752 + //
753 + // The tag regex is quote-aware because `[^>]*>` stops at a `>` inside
754 + // a quoted value, and consent managers routinely ship JSON in a
755 + // data-* attribute.
756 + if ( ! preg_match_all( '#<script\b(?:[^>"\']|"[^"]*"|\'[^\']*\')*>#is', $tag, $tags ) ) {
757 + return false;
758 + }
759 +
760 + foreach ( $tags[0] as $open ) {
761 + // Walk name/value pairs. The name pattern is deliberately
762 + // permissive: a name we cannot recognise (Alpine's `@load`, say)
763 + // must still consume ITS OWN VALUE, or the value gets scanned as
764 + // if it were more attribute names.
765 + if ( ! preg_match_all(
766 + '#\s+([^\s=/>]+)(?:\s*=\s*(?:"[^"]*"|\'[^\']*\'|[^\s>]*))?#s',
767 + substr( $open, 7, -1 ),
768 + $found
769 + ) ) {
770 + continue;
771 + }
772 +
773 + foreach ( $found[1] as $name ) {
774 + if ( in_array( strtolower( $name ), self::OPT_OUT_ATTRIBUTES, true ) ) {
775 + return true;
776 + }
777 + }
778 + }
779 +
780 + return false;
781 + }
782 +
783 + private const NON_EXECUTABLE_TYPES = array(
784 + 'application/ld+json',
785 + 'application/json',
786 + 'importmap',
787 + 'speculationrules',
788 + 'text/template',
789 + 'text/x-template',
790 + 'text/xspeed-delayed',
791 + // A consent manager parks a blocked third-party script here and
792 + // swaps the type back only once the visitor has agreed. Whatever we
793 + // do to such a tag we do on behalf of a decision the visitor has not
794 + // made yet, so the only correct move is to leave it alone. (#274)
795 + 'text/plain',
796 + );
797 +
798 + /**
799 + * The `type` attribute, quoted OR unquoted, anchored to attribute
800 + * position — a required leading whitespace, never a bare `\b`.
801 + *
802 + * The anchoring matters twice over. `\btype` also matches the tail of
803 + * any hyphenated `data-…-type` attribute (a `-` is a non-word char, so
804 + * the boundary sits inside the name — the same #273 class as `src`),
805 + * and it matches a `type=` sitting INSIDE another attribute's value
806 + * (`onload="this.type='done'"`). Requiring whitespace before the name
807 + * rules both out: attributes are whitespace-separated, while `.type`
808 + * and `-type` never are. The unquoted branch exists because
809 + * `type=text/javascript` is valid HTML: a quoted-only pattern left it
810 + * standing, the parking type appended after it lost the
811 + * first-occurrence race, and the snippet executed immediately AND
812 + * replayed on interaction — every vendor event fired twice.
813 + */
814 + private const TYPE_ATTR_RE = '#\stype\s*=\s*(?:(["\'])(.*?)\1|([^\s>]+))#is';
815 +
816 + /**
817 + * `type` values a parked tag need not remember: the replay default is
818 + * already JavaScript, so stashing these would only fatten the markup.
819 + */
820 + private const DEFAULT_JS_TYPES = array(
821 + 'text/javascript',
822 + 'application/javascript',
823 + );
824 +
825 + /**
826 + * Read a tag's `type` attribute value, lowercased and trimmed.
827 + *
828 + * @param string $haystack Full tag or its attribute string.
829 + * @return string '' when no type attribute is present.
830 + */
831 + private static function extract_type( string $haystack ): string {
832 + if ( ! preg_match( self::TYPE_ATTR_RE, $haystack, $m ) ) {
833 + return '';
834 + }
835 + $value = ( isset( $m[3] ) && '' !== $m[3] ) ? $m[3] : $m[2];
836 + return strtolower( trim( $value ) );
837 + }
838 +
839 + /**
840 + * Rewrite an inline tag's attribute string for parking: strip its own
841 + * `type`, stash a non-default one in `data-xs-type` (the bootstrap
842 + * restores it on replay, so a parked `type="module"` comes back as a
843 + * module rather than a classic script — #274), and append the parking
844 + * marker pair.
845 + *
846 + * @param string $attrs Raw attribute string (everything between
847 + * `<script` and `>`).
848 + */
849 + private static function park_type_attrs( string $attrs ): string {
850 + $orig = self::extract_type( $attrs );
851 + $attrs = (string) preg_replace( self::TYPE_ATTR_RE, '', $attrs );
852 + $stash = '';
853 + if ( '' !== $orig && ! in_array( $orig, self::DEFAULT_JS_TYPES, true ) ) {
854 + // MIME-ish charset only — a type value is never markup, and this
855 + // string is re-emitted inside a double-quoted attribute.
856 + $orig = (string) preg_replace( '#[^a-z0-9/+.\-]#', '', $orig );
857 + if ( '' !== $orig ) {
858 + $stash = ' data-xs-type="' . $orig . '"';
859 + }
860 + }
861 + return $attrs . $stash . ' type="text/xspeed-delayed" data-xs-delay="1"';
862 + }
863 +
864 + /**
865 + * URL fragments that must keep a live src no matter what. The enqueue
866 + * path guards these by handle (ALWAYS_EXCLUDED_HANDLES), but a buffer
867 + * pass only ever sees a URL, so the same protection is re-expressed
868 + * here. Without this the admin bundle could be delayed on a frontend
869 + * render and the dashboard would not mount.
870 + */
871 + private const ALWAYS_EXCLUDED_SRC = array(
872 + '/plugins/xspeed/assets/',
873 + '/wp-includes/js/dist/hooks',
874 + '/wp-includes/js/dist/i18n',
875 + );
876 +
877 + /**
878 + * Delay `<script src>` tags that never passed through wp_enqueue_script.
879 + *
880 + * `delay_script_tag()` hooks `script_loader_tag`, so it only ever sees
881 + * enqueued scripts. Analytics, pixels, chat widgets and most third-party
882 + * embeds are printed straight into `wp_head` / `wp_footer` as literal
883 + * markup, bypassing that filter entirely — and those are exactly the
884 + * scripts most worth delaying. On the site that surfaced this, 39
885 + * enqueued scripts were correctly delayed while one un-enqueued
886 + * analytics tag still downloaded 441 KB: 98% of the page's JS payload.
887 + *
888 + * Runs on the finished page buffer via `xspeed_cache_final_html`, so the
889 + * rewrite is baked into the cached HTML and replays on every static hit
890 + * (where PHP never boots). Deliberately conservative — it rewrites only
891 + * `src`, leaves inline code to the enqueue path, and skips any tag whose
892 + * `type` marks it as data rather than code.
893 + *
894 + * @param string $html Complete page HTML.
895 + */
896 + public static function delay_raw_script_tags( $html ): string {
897 + if ( ! is_string( $html ) || '' === $html ) {
898 + return (string) $html;
899 + }
900 + if ( self::skip_in_non_frontend_context() ) {
901 + return $html;
902 + }
903 + $opts = self::opts();
904 + if ( empty( $opts['delay_js'] ) ) {
905 + return $html;
906 + }
907 +
908 + return (string) preg_replace_callback(
909 + '#<script\b[^>]*>#i',
910 + static function ( array $m ): string {
911 + $tag = $m[0];
912 +
913 + // Already handled by the enqueue-path filter.
914 + if ( false !== stripos( $tag, 'data-xs-delay' ) || false !== stripos( $tag, 'data-xs-src' ) ) {
915 + return $tag;
916 + }
917 +
918 + // The author asked every optimizer to leave this tag alone.
919 + // Checked before src/type: it needs neither, so an
920 + // un-enqueued banner printed straight into wp_head is
921 + // covered the same as an enqueued one.
922 + //
923 + // Both checks, because they disagree on purpose and either
924 + // saying "leave it" is the safe answer. tag_opts_out() is
925 + // dev's (#456) and also drives the late re-check at #469;
926 + // carries_optimizer_opt_out() reads attribute NAMES across
927 + // every opening tag, so it is not fooled by a marker sitting
928 + // inside a quoted value or an inline body, and it knows the
929 + // other optimizers' markers.
930 + if ( self::tag_opts_out( $tag ) || self::carries_optimizer_opt_out( $tag ) ) {
931 + return $tag;
932 + }
933 +
934 + // No src → inline code. The enqueue path owns those; a
935 + // buffer rewrite here would have to reason about execution
936 + // order it cannot see.
937 + // `(?<![-\w])` not `\b` — see the note on the enqueue-path
938 + // rewrite above. With `\b`, a tag whose ONLY url lives in
939 + // `data-cmplz-src` (a consent-blocked script, no real src at
940 + // all) read as an external script here, and the rewrite
941 + // below then mangled that attribute. (#273)
942 + if ( ! preg_match( '#(?<![-\w])src\s*=\s*(["\'])(.*?)\1#is', $tag, $src_m ) ) {
943 + return $tag;
944 + }
945 + $src = $src_m[2];
946 +
947 + // Data, not code.
948 + if ( in_array( self::extract_type( $tag ), self::NON_EXECUTABLE_TYPES, true ) ) {
949 + return $tag;
950 + }
951 +
952 + foreach ( self::ALWAYS_EXCLUDED_SRC as $needle ) {
953 + if ( false !== stripos( $src, $needle ) ) {
954 + return $tag;
955 + }
956 + }
957 +
958 + // An ENQUEUED script reaches this sweep too: the enqueue-path
959 + // filter leaves an EXCLUDED tag unmarked, and unmarked is all
960 + // this pass can see. Judging it on its URL alone re-delays the
961 + // very script the exclusion protected — and a handle is not
962 + // generally in its own URL, which is the shape Complianz
963 + // (`cmplz-cookiebanner`), NotificationX (`notificationx-public`)
964 + // and jQuery (`jquery-core`) all have. A site with jquery-core
965 + // excluded still shipped jQuery delayed, and every inline
966 + // `jQuery(...)` on the page threw "jQuery is not defined".
967 + // WordPress prints `id="<handle>-js"` on every enqueued
968 + // script, so the handle is right there in the tag. (#275)
969 + //
970 + // The lookbehind matters: `data-id="cmplz-cookiebanner-js"` is
971 + // somebody's own attribute, not the handle, and reading it as
972 + // one would shield a script nobody excluded.
973 + //
974 + // Merge note for #374: if a URL->handle map built from
975 + // wp_scripts() lands first, resolve through that and keep
976 + // this as the FALLBACK rather than replacing it. The map is
977 + // keyed on the REGISTERED src, and Minifier::rewrite_script()
978 + // rewrites a local script's URL to a hashed /cache/xspeed/min/
979 + // path at output time -- which is why remember_original_src()
980 + // exists. So with minify_js on, the map misses every minified
981 + // script and an excluded one would be re-delayed here. The
982 + // `id` survives that rewrite.
983 + $tag_handle = '';
984 + if ( preg_match( '#(?<![-\w])id\s*=\s*(["\'])(.*?)\1#is', $tag, $id_m ) ) {
985 + // WP appends `-js`; anything else is somebody's own id and
986 + // is still worth matching literally.
987 + $tag_handle = (string) preg_replace( '/-js$/', '', trim( $id_m[2] ) );
988 + }
989 +
990 + if ( self::is_excluded_script( $tag_handle, $src, true ) ) {
991 + return $tag;
992 + }
993 + // The handle is passed to the target test as well, so naming a
994 + // handle in the delay list behaves the same here as it does on
995 + // the enqueue path. The two layers disagreeing on what a target
996 + // means is what made this look like a matching quirk rather
997 + // than a whole layer ignoring the list.
998 + if ( ! self::is_delay_target( $tag_handle, $src ) ) {
999 + return $tag;
1000 + }
1001 + // Mirror of the enqueue-path guard: a handle that inline code
1002 + // reads stays eager unless the user named it. wp_scripts()
1003 + // is still populated at xspeed_cache_final_html time on a
1004 + // MISS, so the registry walk is consultable here too; an
1005 + // unrecoverable handle ('') simply never matches the set.
1006 + if ( '' !== $tag_handle
1007 + && isset( self::inline_bound_handles()[ $tag_handle ] )
1008 + && ! self::is_user_named_target( $tag_handle, $src ) ) {
1009 + return $tag;
1010 + }
1011 +
1012 + return (string) preg_replace(
1013 + '#(?<![-\w])src\s*=\s*(["\'][^"\']*["\'])#i',
1014 + 'data-xs-src=$1 data-xs-delay="1"',
1015 + $tag,
1016 + 1
1017 + );
1018 + },
1019 + $html
1020 + );
1021 + }
1022 +
1023 + /**
1024 + * Delay inline vendor snippets that reference a known third-party host.
1025 + *
1026 + * The pass above rewrites `src` and deliberately leaves inline code
1027 + * alone — but the OFFICIAL install for Clarity, GA, GTM and the Meta
1028 + * pixel is an inline loader (`(function(c,l,a,r,i,t,y){…t.src=…})`)
1029 + * with no `src` attribute at all. That snippet executes on every page
1030 + * load, fetches the vendor bundle inside the measurement window, and
1031 + * puts the one host whose Cache-Control the site cannot set straight
1032 + * into the cache-policy and TBT audits. Delaying the enqueue path and
1033 + * the raw-src path while this runs untouched is delaying everything
1034 + * except the tag the feature exists for.
1035 + *
1036 + * The judgment call is the same one KNOWN_THIRD_PARTY_SRC already
1037 + * makes: an inline body that names one of those hosts is that vendor's
1038 + * loader or its config — never something first-party code holds a
1039 + * synchronous reference to. The body is the haystack for the user's
1040 + * exclusion and target lists too, so the same fragment that protects a
1041 + * `src` tag protects its inline install.
1042 + *
1043 + * `document.write` bodies are skipped outright: replayed after the
1044 + * parser has closed the document, a delayed write would replace the
1045 + * page rather than add to it.
1046 + *
1047 + * @param string $html Complete page HTML.
1048 + */
1049 + public static function delay_inline_snippets( $html ): string {
1050 + if ( ! is_string( $html ) || '' === $html ) {
1051 + return (string) $html;
1052 + }
1053 + if ( self::skip_in_non_frontend_context() ) {
1054 + return $html;
1055 + }
1056 + $opts = self::opts();
1057 + if ( empty( $opts['delay_js'] ) ) {
1058 + return $html;
1059 + }
1060 +
1061 + $handle_delayed = self::handle_delay_outcomes( $html );
1062 +
1063 + $out = preg_replace_callback(
1064 + '#<script\b([^>]*)>(.*?)</script>#is',
1065 + static function ( array $m ) use ( $handle_delayed ): string {
1066 + list( $whole, $attrs, $body ) = $m;
1067 +
1068 + if ( '' === trim( $body ) ) {
1069 + return $whole;
1070 + }
1071 +
1072 + // The tag itself asked to be left alone. (#456)
1073 + if ( self::tag_opts_out( $attrs ) ) {
1074 + return $whole;
1075 + }
1076 +
1077 + // Our own replay bootstrap. Its body quotes the delay
1078 + // machinery's own strings, so a pathological user target
1079 + // fragment could match it — and a parked bootstrap means
1080 + // nothing on the page ever replays.
1081 + if ( false !== stripos( $attrs, 'xspeed-delay-bootstrap' ) ) {
1082 + return $whole;
1083 + }
1084 +
1085 + // Already marked, or a real src= — the src passes own those.
1086 + // `(?<![-\w])` for the same reason as above: `data-cmplz-src`
1087 + // must not read as a src. (#273)
1088 + if ( false !== stripos( $attrs, 'data-xs-delay' ) || false !== stripos( $attrs, 'data-xs-src' ) ) {
1089 + return $whole;
1090 + }
1091 + if ( preg_match( '#(?<![-\w])src\s*=\s*(["\']).*?\1#is', $attrs ) ) {
1092 + return $whole;
1093 + }
1094 +
1095 + // Data, a module map, or a consent manager's parked tag.
1096 + if ( in_array( self::extract_type( $attrs ), self::NON_EXECUTABLE_TYPES, true ) ) {
1097 + return $whole;
1098 + }
1099 +
1100 + // A delayed document.write replays after the document has
1101 + // closed and replaces the page. Never delay one.
1102 + if ( false !== stripos( $body, 'document.write' ) ) {
1103 + return $whole;
1104 + }
1105 +
1106 + // Our own inline scripts, by the id they are printed with.
1107 + // The src passes get this for free from the handle prefix,
1108 + // but here the handle is '' — and the facade observer's body
1109 + // names youtube/vimeo, so a user target like "youtube" would
1110 + // park the very script that makes those embeds cheap.
1111 + if ( preg_match( '#(?<![-\w])id\s*=\s*(["\'])xspeed-#i', $attrs ) ) {
1112 + return $whole;
1113 + }
1114 +
1115 + // A handle's own inline blocks follow the handle, not only their
1116 + // body text. The body rule below decided them alone, so a
1117 + // `-js-extra` whose data named a target was parked while its
1118 + // script, kept eager by a URL exclusion, ran first and read an
1119 + // undefined global. (#549)
1120 + //
1121 + // Ahead of the exclusion list on purpose. The handle's own tag
1122 + // was already weighed against it by handle and URL; a body
1123 + // match here would keep the after-code of a delayed script
1124 + // eager, running it before the script it calls.
1125 + if ( preg_match( '#(?<![-\w])id\s*=\s*(["\'])(.+?)-js-(extra|before|after)\1#i', $attrs, $own ) ) {
1126 + $part = strtolower( $own[3] );
1127 + // wp_localize_script data. Early is always safe: it only
1128 + // assigns, and its script cannot run before it.
1129 + if ( 'extra' === $part ) {
1130 + return $whole;
1131 + }
1132 + if ( isset( $handle_delayed[ $own[2] ] ) ) {
1133 + if ( $handle_delayed[ $own[2] ] ) {
1134 + return '<script' . self::park_type_attrs( $attrs ) . '>' . $body . '</script>';
1135 + }
1136 + // The script runs at load, so its `before` code must too.
1137 + // Its `after` code still runs after it if parked, so that
1138 + // one is left to the body rule, like any vendor loader.
1139 + if ( 'before' === $part ) {
1140 + return $whole;
1141 + }
1142 + }
1143 + }
1144 +
1145 + // The body stands in for the URL in the lists the src passes
1146 + // consult — but NOT via is_delay_target(), whose empty-list
1147 + // default is "delay everything". That default is right for a
1148 + // tag with a URL and catastrophic here: it would park every
1149 + // inline script on the page. Inline code is delayed only on a
1150 + // positive identification — the body names a known vendor
1151 + // host, or a fragment the user targeted — and the exclusion
1152 + // list still wins first. A target naming a consent manager
1153 + // lifts the floor here the same way it does for a src tag;
1154 + // without it the same entry delayed the file and left the
1155 + // vendor's inline code eager.
1156 + if ( self::is_excluded_script( '', $body, true ) ) {
1157 + return $whole;
1158 + }
1159 +
1160 + if ( ! self::matches_known_third_party( $body ) && ! self::matches_user_targets( $body ) ) {
1161 + return $whole;
1162 + }
1163 +
1164 + // Replace — not append — any existing type. Attributes keep
1165 + // their FIRST occurrence in HTML, so appending the parking
1166 + // type after the snippet's own `type="text/javascript"`
1167 + // would leave the original executable. A non-default type is
1168 + // stashed in data-xs-type for the bootstrap to restore.
1169 + return '<script' . self::park_type_attrs( $attrs ) . '>' . $body . '</script>';
1170 + },
1171 + $html
1172 + );
1173 + // A PCRE failure (backtrack limit on a huge inline body) returns
1174 + // null — and casting that to '' would serve AND cache a blank page.
1175 + // The unrewritten original is always the safe fallback.
1176 + return null === $out ? $html : $out;
1177 + }
1178 +
1179 + /**
1180 + * Whether each enqueued handle's external tag ended up delayed.
1181 + *
1182 + * Read from the finished HTML rather than recorded as tags are filtered:
1183 + * this runs after every pass that can delay a tag (script_loader_tag, the
1184 + * late opt-out revert, the raw-tag sweep), so the page itself is the only
1185 + * complete answer.
1186 + *
1187 + * @param string $html Complete page HTML.
1188 + * @return array<string,bool> Handle => delayed.
1189 + */
1190 + private static function handle_delay_outcomes( string $html ): array {
1191 + if ( ! preg_match_all( '#<script\b((?:"[^"]*"|\'[^\']*\'|[^>"\'])*)>#i', $html, $m ) ) {
1192 + return array();
1193 + }
1194 + $out = array();
1195 + foreach ( $m[1] as $attrs ) {
1196 + if ( ! preg_match( '#(?<![-\w])id\s*=\s*(["\'])(.+?)-js\1#i', $attrs, $id ) ) {
1197 + continue;
1198 + }
1199 + $out[ $id[2] ] = false !== stripos( $attrs, 'data-xs-delay' ) || false !== stripos( $attrs, 'data-xs-src' );
1200 + }
1201 + return $out;
1202 + }
1203 +
1204 + /**
117 1205 * Inline bootstrap that flips delayed scripts on the first user
118 1206 * interaction. Printed once on wp_footer priority 1000.
119 1207 */
120 1208 public static function print_delay_bootstrap(): void {
@@ -124,38 +1212,59 @@
124 1212 if ( self::$delay_bootstrap_printed ) {
125 1213 return;
126 1214 }
127 1215 self::$delay_bootstrap_printed = true;
128 - // Tiny vanilla bootstrap; keep it self-contained so the page
129 - // has no JS dependencies before the first interaction.
130 - ?>
131 -<script id="xspeed-delay-bootstrap">
132 -(function(){
133 - var events=['mousemove','keydown','touchstart','scroll','wheel'];
134 - var fired=false;
135 - function load(){
136 - if(fired)return;fired=true;
137 - events.forEach(function(e){window.removeEventListener(e,load,{passive:true,capture:true});});
138 - var delayed=document.querySelectorAll('script[data-xs-delay]');
139 - delayed.forEach(function(s){
140 - var n=document.createElement('script');
141 - Array.prototype.slice.call(s.attributes).forEach(function(a){
142 - if(a.name==='data-xs-src'){n.setAttribute('src',a.value);return;}
143 - if(a.name==='data-xs-delay'||a.name==='type')return;
144 - n.setAttribute(a.name,a.value);
145 - });
146 - if(!s.hasAttribute('data-xs-src')){n.text=s.text;}
147 - s.parentNode.replaceChild(n,s);
148 - });
149 - }
150 - events.forEach(function(e){window.addEventListener(e,load,{passive:true,capture:true});});
151 - setTimeout(load,8000);
152 -})();
153 -</script>
154 - <?php
1216 +
1217 + // Failsafe timer for visitors who never interact. 0 disables it
1218 + // entirely (interaction-only), which is what lab tools measure
1219 + // best: a timer that fires inside Lighthouse's / GTmetrix's
1220 + // measurement window loads the "delayed" scripts anyway and
1221 + // inflates the reported TTI, so the delay looks ineffective.
1222 + $opts = self::opts();
1223 + $timeout = isset( $opts['delay_js_timeout'] ) ? (int) $opts['delay_js_timeout'] : 8000;
1224 + $timeout = max( 0, min( 60000, $timeout ) );
1225 +
1226 + // The script is includes/js/delay-bootstrap.js, which also carries
1227 + // the design notes for the lifecycle replay (#494). `npm run build`
1228 + // minifies it into assets/delay-bootstrap.min.js; the timeout goes in
1229 + // place of its one placeholder.
1230 + //
1231 + // The tag goes out through wp_print_inline_script_tag(), like Free's
1232 + // other inline scripts, so a CSP plugin's wp_inline_script_attributes
1233 + // filter can give it a nonce. Printed bare, a nonce CSP blocked it
1234 + // and nothing was ever replayed.
1235 + $js = str_replace( 'XSPEED_DELAY_TIMEOUT', (string) $timeout, self::delay_bootstrap_js() );
1236 + wp_print_inline_script_tag( $js, array( 'id' => 'xspeed-delay-bootstrap' ) );
155 1237 }
156 1238
1239 + /** The delay bootstrap's code, read once per request. */
1240 + private static $delay_bootstrap_js = null;
1241 +
157 1242 /**
1243 + * The built delay bootstrap, without the line that records its source.
1244 + * If the build is missing, the readable source is valid JS too, only
1245 + * larger: printing nothing would leave every delayed script parked for
1246 + * good, because the tags are already rewritten by the time this runs.
1247 + */
1248 + private static function delay_bootstrap_js(): string {
1249 + if ( null !== self::$delay_bootstrap_js ) {
1250 + return self::$delay_bootstrap_js;
1251 + }
1252 + $root = dirname( __DIR__ );
1253 + $built = $root . '/assets/delay-bootstrap.min.js';
1254 + // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents -- a local plugin file, not a remote URL.
1255 + $js = is_readable( $built ) ? (string) file_get_contents( $built ) : '';
1256 + if ( '' !== $js ) {
1257 + $js = (string) preg_replace( '#\A/\*[^\n]*\*/\n#', '', $js );
1258 + } else {
1259 + // phpcs:ignore WordPress.WP.AlternativeFunctions.file_get_contents_file_get_contents -- a local plugin file, not a remote URL.
1260 + $js = (string) file_get_contents( $root . '/includes/js/delay-bootstrap.js' );
1261 + }
1262 + self::$delay_bootstrap_js = trim( $js );
1263 + return self::$delay_bootstrap_js;
1264 + }
1265 +
1266 + /**
158 1267 * Filter: `style_loader_tag` — wrap stylesheets in the
159 1268 * print → onload="all" pattern so they download non-blocking.
160 1269 * Pairs with critical CSS workflows. Adds a <noscript> fallback so
161 1270 * users with JS disabled still get styles applied (via media="all").
@@ -175,12 +1284,109 @@
175 1284 // want to fight with explicit author intent.
176 1285 if ( false === stripos( $tag, 'rel=\'stylesheet\'' ) && false === stripos( $tag, 'rel="stylesheet"' ) ) {
177 1286 return $tag;
178 1287 }
1288 + // No critical CSS for this page: every stylesheet stays blocking.
1289 + //
1290 + // Deferring a stylesheet only helps when something already styles the
1291 + // first screen. Without that, the page paints unstyled and then jumps
1292 + // when the sheets arrive. Measured on the Templately Astoria pages
1293 + // (Elementor and a block theme): CLS 0.43-1.27 and 15-43 points lower
1294 + // on 7 of 8 pages than the same settings without async CSS. The guards
1295 + // below narrow the damage; this one removes it. WP Rocket, LiteSpeed,
1296 + // Jetpack Boost and FlyingPress likewise never defer CSS without
1297 + // critical CSS. (#588)
1298 + if ( ! self::page_has_critical_css() ) {
1299 + return $tag;
1300 + }
1301 + // The stylesheets that lay the page out stay render-blocking.
1302 + //
1303 + // This transform moves a sheet to AFTER first paint. That is the
1304 + // point of it — but a sheet the layout depends on is then missing
1305 + // from the only paint the visitor sees, and the page renders as
1306 + // unstyled HTML (bulleted nav, underlined links) until the swap
1307 + // runs. The pattern is only safe when something already styles the
1308 + // above-the-fold area, i.e. critical CSS — which Free does not
1309 + // generate. Deferring EVERY sheet on a site without it guarantees
1310 + // the flash rather than risking it: on the reported Kadence site
1311 + // all 17 stylesheets were deferred and none was render-blocking,
1312 + // so there was nothing left to paint the page with. (#269)
1313 + if ( self::is_layout_critical_style( $handle ) ) {
1314 + return $tag;
1315 + }
1316 + // A JS-measured layout on this page makes deferral unsafe for EVERY
1317 + // sheet, not just the theme's.
1318 + //
1319 + // Masonry, isotope, packery and the slider libraries lay elements out
1320 + // by MEASURING them and then writing absolute positions. Deferring the
1321 + // stylesheet that sizes those elements means the script measures them
1322 + // unstyled — zero or full-width — computes positions from those wrong
1323 + // numbers, and commits them. The CSS arriving a moment later cannot
1324 + // undo it: the script has already run and does not re-measure. The
1325 + // result is a permanently broken grid (items overlapping, or stranded
1326 + // with a large gap), which is worse than the flash this feature's
1327 + // other guard prevents, because it never resolves itself.
1328 + //
1329 + // This is checked per PAGE rather than per handle deliberately. The
1330 + // script that measures is rarely the one whose handle matches the
1331 + // sheet — Kadence's gallery is styled by
1332 + // `kadence-blocks-advancedgallery` but laid out by core's `masonry` —
1333 + // so pairing handles misses it. Whether a measuring library is present
1334 + // at all is the signal that generalises. (#269)
1335 + if ( self::page_has_js_measured_layout() ) {
1336 + return $tag;
1337 + }
179 1338 // Avoid double-wrapping.
180 1339 if ( false !== stripos( $tag, 'data-xs-async' ) ) {
181 1340 return $tag;
182 1341 }
1342 + // Someone else already made this sheet non-render-blocking.
1343 + //
1344 + // Plugins that ship their own async-CSS handling apply the same
1345 + // media="print" + onload swap we do, and they run on the SAME
1346 + // filter — SureCookie's consent banner does it at style_loader_tag
1347 + // priority 10, ours is priority 20, so its finished tag arrives
1348 + // here looking like a plain stylesheet with no marker of ours.
1349 + //
1350 + // Transforming it again breaks the sheet two ways: the media we'd
1351 + // capture as "the original to restore" is already `print`, so we
1352 + // emit onload="this.media='print'" — a swap to itself that never
1353 + // activates the stylesheet — and we append a SECOND onload
1354 + // attribute, of which the parser honours only the first (ours),
1355 + // discarding the plugin's correct this.media='all'. The banner
1356 + // then mounts unstyled, in both logged-in and logged-out states.
1357 + //
1358 + // An onload handler or a print media on a stylesheet link is only
1359 + // ever this pattern; a genuinely print-only sheet is already off
1360 + // the critical path and gains nothing from us. Either way the
1361 + // right move is to leave the tag alone — the same "don't fight
1362 + // explicit author intent" rule the rel= check above applies. (#216)
1363 + if ( preg_match( '#\bonload\s*=#i', $tag ) ) {
1364 + return $tag;
1365 + }
1366 + if ( preg_match( '#\bmedia\s*=\s*(["\'])\s*print\s*\1#i', $tag ) ) {
1367 + return $tag;
1368 + }
1369 + return self::async_link_markup( $tag );
1370 + }
1371 +
1372 + /**
1373 + * The one place the async-CSS output shape lives: swap the link's media
1374 + * to `print`, restore the original media onload, record it in
1375 + * `data-xs-async`, and re-emit the untouched tag inside `<noscript>` for
1376 + * clients that never run the onload handler.
1377 + *
1378 + * Shared by the enqueue-path filter above and the raw-tag buffer pass
1379 + * below so the two can never drift — Pro's Critical CSS recognises this
1380 + * exact marker to avoid double-wrapping, and a second copy of the
1381 + * pattern is how that kind of contract quietly breaks.
1382 + *
1383 + * Callers own every skip decision (markers, onload, non-screen media);
1384 + * this helper only produces the markup.
1385 + *
1386 + * @param string $tag A `<link rel="stylesheet">` tag deemed safe to defer.
1387 + */
1388 + private static function async_link_markup( string $tag ): string {
183 1389 $async = (string) preg_replace_callback(
184 1390 '#\bmedia\s*=\s*(["\'])([^"\']*)\1#i',
185 1391 static function ( $m ) {
186 1392 $orig = $m[2];
@@ -202,8 +1408,313 @@
202 1408 return $async . '<noscript>' . $tag . '</noscript>';
203 1409 }
204 1410
205 1411 /**
1412 + * Stylesheet hosts that serve FONT CSS — small, render-blocking sheets of
1413 + * `@font-face` rules. The buffer pass below defers only these: a raw
1414 + * cross-origin `<link>` could carry anything, and blindly deferring an
1415 + * unknown vendor's layout CSS from the buffer would reintroduce the
1416 + * unstyled-flash failure async_style_tag()'s guards exist to prevent.
1417 + * Font CSS is the safe subset — text renders in a fallback face and swaps,
1418 + * which is exactly what `font-display: swap` does on purpose.
1419 + */
1420 + private const FONT_CSS_HOSTS = array(
1421 + 'fonts.googleapis.com',
1422 + 'fonts.bunny.net',
1423 + 'use.typekit.net',
1424 + 'p.typekit.net',
1425 + 'fonts.cdnfonts.com',
1426 + );
1427 +
1428 + /**
1429 + * The font-CSS host allowlist, filtered and normalised.
1430 + *
1431 + * @return string[] Lowercase hostnames.
1432 + */
1433 + private static function font_css_hosts(): array {
1434 + /**
1435 + * Hosts whose stylesheet links the async-CSS buffer pass rewrites to
1436 + * the non-blocking print → onload pattern. Only font-CSS providers
1437 + * belong here: every listed host's sheets are safe to load late
1438 + * because they only add `@font-face` rules.
1439 + *
1440 + * @param string[] $hosts Hostnames (exact match, case-insensitive).
1441 + */
1442 + $hosts = (array) apply_filters( 'xspeed_async_css_font_hosts', self::FONT_CSS_HOSTS );
1443 +
1444 + return array_map( 'strtolower', array_map( 'strval', $hosts ) );
1445 + }
1446 +
1447 + /**
1448 + * Media values that never apply to a screen paint. A sheet restricted to
1449 + * one of these is not render-blocking for screen, so deferring it saves
1450 + * nothing — and `print` in particular is either a genuine print sheet or
1451 + * somebody's finished async pattern, both of which must be left alone.
1452 + */
1453 + private const NON_SCREEN_MEDIA = array(
1454 + 'print',
1455 + 'speech',
1456 + 'aural',
1457 + 'braille',
1458 + 'embossed',
1459 + 'handheld',
1460 + 'projection',
1461 + 'tty',
1462 + 'tv',
1463 + );
1464 +
1465 + /**
1466 + * Filter: `xspeed_cache_final_html` — defer RAW font-CSS stylesheet links
1467 + * that never passed through wp_enqueue_style.
1468 + *
1469 + * `async_style_tag()` hooks `style_loader_tag`, so it only ever sees
1470 + * enqueued stylesheets. Themes and font plugins print Google Fonts (and
1471 + * Bunny, Typekit, CDNFonts) as literal
1472 + * `<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=…">`
1473 + * markup in the head — on the site that surfaced this, four such tags —
1474 + * and each one stays render-blocking with no plugin lever. Unused CSS
1475 + * skips cross-origin hrefs by design, so nothing else picks them up.
1476 + *
1477 + * Runs on the finished page buffer, so the rewrite is baked into the
1478 + * cached HTML and replays on every static hit. Deliberately narrow: only
1479 + * links whose host is on the font-CSS allowlist are touched — see
1480 + * FONT_CSS_HOSTS. Same-origin links (no host, or the site's own) never
1481 + * match the allowlist and are untouched.
1482 + *
1483 + * @param string $html Complete page HTML.
1484 + */
1485 + public static function async_raw_font_css_links( $html ): string {
1486 + if ( ! is_string( $html ) || '' === $html ) {
1487 + return (string) $html;
1488 + }
1489 + if ( self::skip_in_non_frontend_context() ) {
1490 + return $html;
1491 + }
1492 + $opts = self::opts();
1493 + if ( empty( $opts['async_css'] ) ) {
1494 + return $html;
1495 + }
1496 +
1497 + // Never rewrite inside a <noscript>. That block IS the no-JS
1498 + // fallback — its <link> is a plain blocking stylesheet on purpose,
1499 + // and async_style_tag() itself emits one for every sheet it defers.
1500 + // Rewriting it would nest <noscript> (invalid; the parser closes the
1501 + // outer block at the first </noscript>) and hand no-JS visitors a
1502 + // media="print" sheet whose onload never runs: no stylesheet at all.
1503 + // Splitting the buffer on <noscript> spans and rewriting only the
1504 + // slices between them also makes the pass idempotent against
1505 + // whatever an earlier pass emitted.
1506 + $parts = preg_split(
1507 + '#(<noscript\b[^>]*>.*?</noscript\s*>)#is',
1508 + $html,
1509 + -1,
1510 + PREG_SPLIT_DELIM_CAPTURE
1511 + );
1512 +
1513 + // preg_split failed (pathological buffer / backtrack limit). Without
1514 + // the split we cannot tell a fallback link from a live one, so leave
1515 + // the page untouched — a few blocking font sheets beat a broken
1516 + // no-JS fallback.
1517 + if ( ! is_array( $parts ) ) {
1518 + return $html;
1519 + }
1520 +
1521 + foreach ( $parts as $i => $part ) {
1522 + // Odd indices are the captured <noscript> blocks.
1523 + if ( 1 === $i % 2 || '' === $part ) {
1524 + continue;
1525 + }
1526 + $parts[ $i ] = self::async_font_links_in_slice( $part );
1527 + }
1528 +
1529 + return implode( '', $parts );
1530 + }
1531 +
1532 + /**
1533 + * Rewrite the font-CSS links in one <noscript>-free slice of the buffer.
1534 + *
1535 + * @param string $html Slice of page HTML with no <noscript> spans.
1536 + */
1537 + private static function async_font_links_in_slice( string $html ): string {
1538 + $hosts = self::font_css_hosts();
1539 +
1540 + $out = preg_replace_callback(
1541 + '#<link\b[^>]*>#i',
1542 + static function ( array $m ) use ( $hosts ): string {
1543 + $tag = $m[0];
1544 +
1545 + // Only plain stylesheets — never preload/alternate/anything
1546 + // carrying explicit author intent. `(?<![-\w])` not `\b`, so
1547 + // a `data-rel=` attribute can never read as the rel — same
1548 + // reason the delay passes spell src that way. (#273)
1549 + if ( ! preg_match( '#(?<![-\w])rel\s*=\s*(["\']?)\s*stylesheet\s*\1#i', $tag ) ) {
1550 + return $tag;
1551 + }
1552 +
1553 + // Already deferred (either marker spelling — ours and Pro's),
1554 + // or explicitly opted out by the theme.
1555 + foreach ( array( 'data-xs-async', 'data-xspeed-async', 'data-xspeed-keep' ) as $marker ) {
1556 + if ( false !== stripos( $tag, $marker ) ) {
1557 + return $tag;
1558 + }
1559 + }
1560 +
1561 + // An onload handler on a stylesheet link is only ever
1562 + // somebody's finished async pattern — same rule as
1563 + // async_style_tag(). (#216)
1564 + if ( preg_match( '#(?<![-\w])onload\s*=#i', $tag ) ) {
1565 + return $tag;
1566 + }
1567 +
1568 + // A sheet that never applies on screen is not blocking paint.
1569 + if ( preg_match( '#(?<![-\w])media\s*=\s*(["\'])([^"\']*)\1#i', $tag, $mm )
1570 + && in_array( strtolower( trim( $mm[2] ) ), self::NON_SCREEN_MEDIA, true ) ) {
1571 + return $tag;
1572 + }
1573 +
1574 + if ( ! preg_match( '#(?<![-\w])href\s*=\s*(["\'])([^"\']+)\1#i', $tag, $hm ) ) {
1575 + return $tag;
1576 + }
1577 + // No host means a relative URL — same-origin, and the enqueue
1578 + // path's business if it is anybody's.
1579 + $host = strtolower( (string) wp_parse_url( $hm[2], PHP_URL_HOST ) );
1580 + if ( '' === $host || ! in_array( $host, $hosts, true ) ) {
1581 + return $tag;
1582 + }
1583 +
1584 + return self::async_link_markup( $tag );
1585 + },
1586 + $html
1587 + );
1588 +
1589 + // A PCRE failure returns null — the unrewritten slice is the safe
1590 + // fallback, never an empty page.
1591 + return null === $out ? $html : $out;
1592 + }
1593 +
1594 + /**
1595 + * Whether a stylesheet handle carries the page's layout, and so must
1596 + * keep blocking the first paint.
1597 + *
1598 + * Two families qualify:
1599 + *
1600 + * - The ACTIVE THEME's own sheets. A theme stylesheet is the page's
1601 + * layout by definition; without it the document paints as unstyled
1602 + * HTML. Resolved from the live theme's stem (`kadence` →
1603 + * `kadence-global`, `kadence-header`, …) plus the handles WordPress
1604 + * itself registers for a theme, so this holds for any theme rather
1605 + * than a hard-coded list.
1606 + * - WordPress' own BLOCK and layout sheets (`wp-block-library`,
1607 + * `global-styles`, `classic-theme-styles`). These style block
1608 + * content on the front end and are as structural as the theme's.
1609 + * - A page builder's GRID sheets: the rows, columns, sections and
1610 + * containers everything else sits in (`kadence-blocks-rowlayout`,
1611 + * `kadence-blocks-column`, `elementor-frontend`, `elementor-post-N`).
1612 + * On a builder page these lay out the hero, not the theme. Deferred,
1613 + * the hero painted as one stacked column and then snapped into its
1614 + * grid: CLS 0.665 on desktop, from one row.
1615 + *
1616 + * Everything else — plugin sheets, icon fonts, buttons, forms, the
1617 + * builder's per-widget sheets, the long tail that makes async CSS worth
1618 + * having — is still deferred, so the optimization keeps most of its
1619 + * benefit.
1620 + *
1621 + * A site WITH critical CSS can defer these too; that is what the
1622 + * `xspeed_async_css_layout_critical` filter is for.
1623 + *
1624 + * Pure aside from the theme lookup — unit-tested via the filter.
1625 + *
1626 + * @param string $handle Stylesheet handle from `style_loader_tag`.
1627 + */
1628 + public static function is_layout_critical_style( string $handle ): bool {
1629 + $handle = strtolower( $handle );
1630 +
1631 + // Core's front-end block + global styles.
1632 + $core = array(
1633 + 'wp-block-library',
1634 + 'wp-block-library-theme',
1635 + 'global-styles',
1636 + 'classic-theme-styles',
1637 + );
1638 + $critical = in_array( $handle, $core, true ) || self::is_builder_grid_style( $handle );
1639 +
1640 + // The active theme's own sheets.
1641 + //
1642 + // Matched on the theme stem, but NOT as a bare prefix: a plugin from
1643 + // the same vendor shares it (the Kadence theme is `kadence`, while
1644 + // `kadence-blocks-image` and `kadence-fonts-gfonts` come from the
1645 + // Kadence Blocks PLUGIN and a webfont loader). Treating every such
1646 + // sheet as layout-critical would leave almost nothing deferred and
1647 + // quietly undo the feature; the builder's grid sheets are caught
1648 + // above by what they do, not whose they are. So the stem must be
1649 + // followed by a recognised theme-area segment, which is how themes
1650 + // name their split sheets.
1651 + if ( ! $critical && function_exists( 'get_template' ) ) {
1652 + $areas = array(
1653 + 'style',
1654 + 'global',
1655 + 'header',
1656 + 'content',
1657 + 'footer',
1658 + 'main',
1659 + 'layout',
1660 + 'base',
1661 + 'core',
1662 + 'theme',
1663 + 'woocommerce',
1664 + );
1665 + foreach ( array( get_template(), get_stylesheet() ) as $stem ) {
1666 + $stem = strtolower( (string) $stem );
1667 + if ( '' === $stem ) {
1668 + continue;
1669 + }
1670 + if ( $handle === $stem ) {
1671 + $critical = true;
1672 + break;
1673 + }
1674 + foreach ( $areas as $area ) {
1675 + if ( $handle === $stem . '-' . $area ) {
1676 + $critical = true;
1677 + break 2;
1678 + }
1679 + }
1680 + }
1681 + }
1682 +
1683 + /**
1684 + * Whether this stylesheet must keep blocking the first paint.
1685 + *
1686 + * Return false for a handle to let async CSS defer it anyway — the
1687 + * right call on a site that ships critical CSS. Return true to
1688 + * protect an additional sheet the layout depends on.
1689 + *
1690 + * @param bool $critical Whether the sheet is treated as layout-critical.
1691 + * @param string $handle The stylesheet handle.
1692 + */
1693 + return (bool) apply_filters( 'xspeed_async_css_layout_critical', $critical, $handle );
1694 + }
1695 +
1696 + /**
1697 + * Whether a handle is a page builder's grid sheet.
1698 + *
1699 + * Matched on the last segment of the handle, so a builder that names its
1700 + * row sheet `acme-blocks-row-layout` is covered without being listed. The
1701 + * segments are the ones that only ever carry structure; a button, image
1702 + * or form sheet styles an element inside the grid, and the grid holds its
1703 + * place while that sheet loads.
1704 + *
1705 + * @param string $handle Lowercase stylesheet handle.
1706 + */
1707 + private static function is_builder_grid_style( string $handle ): bool {
1708 + if ( preg_match( '#(?:^|-)(?:rowlayout|row-layout|column|columns|container|section|grid)$#', $handle ) ) {
1709 + return true;
1710 + }
1711 + // Builders whose grid lives in a sheet named after the builder or the
1712 + // post, not after a structural element.
1713 + return (bool) preg_match( '#^(?:elementor-frontend|elementor-post-\d+|fl-builder-layout(?:-\d+)?|generateblocks)$#', $handle );
1714 + }
1715 +
1716 + /**
206 1717 * Filter: `style_loader_src` + `script_loader_src` — strip the
207 1718 * ?ver=X.Y query string that WP appends for cache busting. Some
208 1719 * CDNs / reverse proxies cache better when the URL has no query.
209 1720 *
@@ -209,8 +1720,27 @@
209 1720 *
210 1721 * Skip URLs whose query carries non-ver params — those might be
211 1722 * intentional (e.g. a CDN providing per-image transforms).
212 1723 *
1724 + * `ver` is load-bearing on one class of asset: a file a plugin
1725 + * REGENERATES IN PLACE. Complianz rewrites
1726 + * uploads/complianz/css/banner-1-optin.css whenever the banner is
1727 + * edited, Beaver Builder rewrites uploads/bb-plugin/cache/<post>-layout.css
1728 + * on every layout save, Elementor uploads/elementor/css/post-<id>.css on
1729 + * publish. The path never changes, so `?ver=<timestamp|hash>` is the only
1730 + * thing telling a browser — or our own Browser Cache `immutable` rule — to
1731 + * refetch. Strip it and the old styling is served until the browser cache
1732 + * gives up, which for us is a year. So anything under the uploads root
1733 + * keeps its version.
1734 + *
1735 + * Release assets under plugins/, themes/ and core are still stripped, but
1736 + * not because they are safe: an update overwrites the same path there too,
1737 + * and only `?ver=` changed. The difference is frequency, not mechanism — a
1738 + * plugin update lands rarely and is expected to, a banner edit is a setting
1739 + * the user just changed and expects to see. Stripping is the feature the
1740 + * toggle is for; with Browser Cache on it is what the user is buying, and
1741 + * `docs/user/minification.md` states the cost. (#276)
1742 + *
213 1743 * @param string $src
214 1744 */
215 1745 public static function strip_version_query( $src ): string {
216 1746 if ( ! is_string( $src ) || '' === $src ) {
@@ -223,17 +1753,46 @@
223 1753 if ( ! is_array( $parts ) || empty( $parts['query'] ) ) {
224 1754 return $src;
225 1755 }
226 1756 parse_str( $parts['query'], $query );
227 - if ( ! is_array( $query ) ) {
1757 + if ( ! is_array( $query ) || ! array_key_exists( 'ver', $query ) ) {
228 1758 return $src;
229 1759 }
1760 +
1761 + $strip = ! self::is_regenerated_asset( $parts );
1762 +
1763 + /**
1764 + * Whether Remove Query Strings drops `?ver` from this asset URL.
1765 + *
1766 + * False by default under the uploads root, where page builders and
1767 + * consent plugins rewrite generated CSS/JS in place and `ver` is its
1768 + * only cache-buster. Return false to protect a generator that writes
1769 + * somewhere else, true to force stripping.
1770 + *
1771 + * @param bool $strip Whether `ver` will be removed.
1772 + * @param string $src The asset URL as enqueued.
1773 + */
1774 + if ( ! apply_filters( 'xspeed_strip_asset_version', $strip, $src ) ) {
1775 + return $src;
1776 + }
1777 +
230 1778 // Only strip 'ver' — keep anything else the asset URL needs.
231 1779 unset( $query['ver'] );
232 1780 $new_query = http_build_query( $query );
233 - $new_url = ( $parts['scheme'] ?? 'http' ) . '://' . ( $parts['host'] ?? '' );
234 - if ( isset( $parts['port'] ) ) {
235 - $new_url .= ':' . $parts['port'];
1781 +
1782 + // Rebuild the authority only when the source had one. An enqueued
1783 + // src is not always absolute: `//cdn.example/x.css` says "the
1784 + // page's own scheme", and defaulting that to http:// is mixed
1785 + // content an https page blocks outright; `/wp-includes/x.js` has no
1786 + // host at all, and pasting one in produced `http:///wp-includes/…`,
1787 + // which resolves nowhere.
1788 + $new_url = '';
1789 + if ( isset( $parts['host'] ) && '' !== $parts['host'] ) {
1790 + $new_url = isset( $parts['scheme'] ) ? $parts['scheme'] . '://' : '//';
1791 + $new_url .= $parts['host'];
1792 + if ( isset( $parts['port'] ) ) {
1793 + $new_url .= ':' . $parts['port'];
1794 + }
236 1795 }
237 1796 $new_url .= $parts['path'] ?? '';
238 1797 if ( '' !== $new_query ) {
239 1798 $new_url .= '?' . $new_query;
@@ -244,8 +1803,80 @@
244 1803 return $new_url;
245 1804 }
246 1805
247 1806 /**
1807 + * Memoised uploads root, see uploads_base(). Cleared by reset_state().
1808 + *
1809 + * @var array{host:string,path:string}|null
1810 + */
1811 + private static $uploads_base = null;
1812 +
1813 + /**
1814 + * The uploads root as a URL host + PATH, read from wp_get_upload_dir()
1815 + * rather than hardcoded so a moved uploads dir, the `UPLOADS` constant and
1816 + * the legacy multisite `/files/` layout all work.
1817 + *
1818 + * On multisite wp_get_upload_dir() answers with the per-site
1819 + * `…/uploads/sites/<id>`. Generated assets live under the network root
1820 + * too, so the suffix comes off and the whole tree matches.
1821 + *
1822 + * @return array{host:string,path:string}
1823 + */
1824 + private static function uploads_base(): array {
1825 + if ( null !== self::$uploads_base ) {
1826 + return self::$uploads_base;
1827 + }
1828 + $base = '';
1829 + if ( function_exists( 'wp_get_upload_dir' ) ) {
1830 + $dir = wp_get_upload_dir();
1831 + $base = is_array( $dir ) && isset( $dir['baseurl'] ) ? (string) $dir['baseurl'] : '';
1832 + }
1833 + $host = '';
1834 + $path = '';
1835 + if ( '' !== $base ) {
1836 + $host = strtolower( (string) wp_parse_url( $base, PHP_URL_HOST ) );
1837 + $path = (string) wp_parse_url( $base, PHP_URL_PATH );
1838 + }
1839 + $path = (string) preg_replace( '#/sites/\d+/?$#', '', rtrim( $path, '/' ) );
1840 + if ( '' === $path && '' === $host ) {
1841 + // Unreadable. An empty prefix would match every asset on the
1842 + // site, so fall back to where uploads normally is.
1843 + $path = '/wp-content/uploads';
1844 + }
1845 + self::$uploads_base = array(
1846 + 'host' => $host,
1847 + 'path' => $path,
1848 + );
1849 + return self::$uploads_base;
1850 + }
1851 +
1852 + /**
1853 + * Does this URL sit under the uploads root — i.e. is it a file some plugin
1854 + * generates at runtime and rewrites in place?
1855 + *
1856 + * @param array<string,mixed> $parts wp_parse_url() output for the asset.
1857 + */
1858 + private static function is_regenerated_asset( array $parts ): bool {
1859 + $base = self::uploads_base();
1860 +
1861 + if ( '' !== $base['path'] ) {
1862 + // Path only, never host: a pull-zone CDN, a protocol-relative URL
1863 + // and an http/https flip all leave the path alone.
1864 + $path = (string) ( $parts['path'] ?? '' );
1865 + return '' !== $path && 0 === strpos( $path, $base['path'] . '/' );
1866 + }
1867 +
1868 + // Uploads AT the root of their own domain — an offload plugin
1869 + // pointing `upload_url_path` at https://cdn.example.com. There is no
1870 + // prefix left to test, and testing the path anyway would have read
1871 + // every generated file on that CDN as an ordinary release asset and
1872 + // stripped the one thing telling a browser it had changed. The host
1873 + // is the whole answer here: everything served from it is an upload.
1874 + $host = strtolower( (string) ( $parts['host'] ?? '' ) );
1875 + return '' !== $host && $host === $base['host'];
1876 + }
1877 +
1878 + /**
248 1879 * Defensive context guard for filter callbacks. Mirrors the registration-
249 1880 * time bail in Minifier::__construct() so a late context flip (admin page
250 1881 * render kicked off mid-request, REST_REQUEST set after plugins_loaded,
251 1882 * etc.) doesn't let frontend tag rewrites leak into wp-admin / AJAX /
@@ -284,12 +1915,231 @@
284 1915 'wp-url',
285 1916 'wp-api-fetch',
286 1917 );
287 1918
288 - private static function is_excluded_script( string $handle, string $src ): bool {
1919 + /**
1920 + * Consent managers are never deferred, and never delayed by a broad
1921 + * setting — only a delay_js_targets entry that NAMES the vendor lifts
1922 + * the floor (see user_named_consent_manager()); the
1923 + * `xspeed_js_exclusion_floor` filter remains the code-level override.
1924 + *
1925 + * A consent banner is drawn by JavaScript, and it is the one thing on
1926 + * the page that has to appear before anything else happens. Delay it
1927 + * and a visitor who lands, reads and leaves without touching the page
1928 + * is never asked — on an opt-in configuration the site then ran
1929 + * without ever offering the choice.
1930 + *
1931 + * The editable list cannot carry this. A stored value replaces the
1932 + * schema default outright (Settings_Manager::get()), so widening that
1933 + * default would reach fresh installs only, and clearing the textarea
1934 + * would drop the protection again. Same floor pattern as
1935 + * Server_Rules::COOKIE_FLOOR. Trim or extend it through
1936 + * `xspeed_js_exclusion_floor`.
1937 + *
1938 + * A URL token cannot survive a rewrite of that URL: Minify JS rewrites a
1939 + * local script to a hashed /cache/xspeed/min/ path, and Combine JS folds
1940 + * it into a bundle. On the enqueue path original_src() gives the pre-minify
1941 + * URL back, but the buffer sweep has only the tag -- so with Minify JS on
1942 + * and the `id` stripped, a banner shipped un-minified is not recognised.
1943 + * Documented in docs/user/minification.md rather than papered over.
1944 + *
1945 + * Each entry goes through target_matches(): an exact handle OR a
1946 + * case-insensitive URL substring. Both passes can match either — the
1947 + * enqueue path is handed the handle, and the buffer sweep reads it back
1948 + * out of the tag's `id`. A URL token additionally covers a banner that
1949 + * was never enqueued at all, which is how Cookiebot prints itself. (#275)
1950 + */
1951 + private const CONSENT_MANAGER_FLOOR = array(
1952 + // Prefer a plugin-directory or vendor-host URL token over a handle.
1953 + // A handle is only readable on the enqueue path and, on the buffer
1954 + // sweep, only if the tag still carries the `id` WordPress prints —
1955 + // which another plugin can strip. A URL token matches on both passes
1956 + // and covers a banner that was never enqueued at all. (#275 QA)
1957 +
1958 + // CookieYes / GDPR Cookie Consent. Handle and plugin directory are
1959 + // the same string, so this covers both paths.
1960 + 'cookie-law-info',
1961 + // Complianz: the plugin directory, covering -gdpr and -gdpr-premium.
1962 + // Was the `cmplz-cookiebanner` handle, which needed the `id` tag.
1963 + 'complianz',
1964 + // NotificationX runs its GDPR cookie notice off the same handle as
1965 + // every other notification, so excluding it excludes them all. That
1966 + // is what the plugin's own team asked for. Directory token covers
1967 + // the Pro build too; was the `notificationx-public` handle.
1968 + 'notificationx',
1969 + // Cookiebot prints its loader straight into wp_head, so only the
1970 + // buffer sweep ever sees it. This is the token Cookiebot's own WP
1971 + // Rocket and LiteSpeed integrations exclude.
1972 + 'consent.cookiebot.com',
1973 + // Cookie Notice — named in the original report and one of the most
1974 + // installed consent plugins. Its banner is enqueued from
1975 + // /plugins/cookie-notice/js/front.min.js.
1976 + 'cookie-notice',
1977 + // Cookie Notice in Cookie Compliance mode prints a different loader,
1978 + // whose host is overridable via CN_APP_WIDGET_URL — so key on the
1979 + // filename, not the CDN host.
1980 + 'hu-banner',
1981 + // Moove GDPR Cookie Compliance. Directory token: its handle
1982 + // (`moove_gdpr_frontend`) does not appear in its own URL.
1983 + 'gdpr-cookie-compliance',
1984 + // Termly's resource blocker, which also covers the legacy embed.
1985 + 'app.termly.io',
1986 + // Usercentrics, reached three ways: Cookiebot's UC mode
1987 + // (web.cmp.usercentrics.eu), Termageddon (app.usercentrics.eu) and
1988 + // the privacy proxy.
1989 + 'usercentrics.eu',
1990 + // Iubenda: both the consent solution and the consent database SDK.
1991 + 'cdn.iubenda.com',
1992 + // OneTrust. Pasted snippet rather than a wordpress.org plugin, so
1993 + // this is the SDK host rather than a verified plugin path.
1994 + 'cdn.cookielaw.org',
1995 + // Borlabs is commercial and renames its files per release; the
1996 + // vendor's own guidance is that this string stays in every path.
1997 + 'borlabs-cookie',
1998 + // Real Cookie Banner, free and pro. Its anti-adblock mode serves the
1999 + // banner from an anonymised path that no URL token can match — use
2000 + // `xspeed_js_exclusion_floor` to add the handle on such a site.
2001 + 'real-cookie-banner',
2002 + // SureCookie.
2003 + 'surecookie',
2004 + );
2005 +
2006 + /**
2007 + * What a site owner types to name each floor entry, and what the admin
2008 + * shows them. Keyed by CONSENT_MANAGER_FLOOR token; a test holds the two
2009 + * in step.
2010 + *
2011 + * The keyword is the part of the token a person would actually write
2012 + * (`cookiebot`, not `consent.cookiebot.com`), and it is always a substring
2013 + * of the token, so an entry that names the vendor this way still matches
2014 + * the vendor's URL. A brand name that appears nowhere in the URL
2015 + * (`cookieyes`, `onetrust`, `cmplz`) is deliberately not a keyword: it
2016 + * could never match the tag, so offering it would promise a lift that
2017 + * cannot happen. The exact handle always works as well.
2018 + *
2019 + * Cookiebot in Usercentrics CMP mode loads from web.cmp.usercentrics.eu,
2020 + * so the floor catches it as Usercentrics and `usercentrics` names it,
2021 + * not `cookiebot`.
2022 + */
2023 + private const CONSENT_MANAGER_NAMES = array(
2024 + 'cookie-law-info' => array( 'label' => 'CookieYes', 'keyword' => 'cookie-law-info' ),
2025 + 'complianz' => array( 'label' => 'Complianz', 'keyword' => 'complianz' ),
2026 + 'notificationx' => array( 'label' => 'NotificationX', 'keyword' => 'notificationx' ),
2027 + 'consent.cookiebot.com' => array( 'label' => 'Cookiebot', 'keyword' => 'cookiebot' ),
2028 + 'cookie-notice' => array( 'label' => 'Cookie Notice', 'keyword' => 'cookie-notice' ),
2029 + 'hu-banner' => array( 'label' => 'Cookie Notice (Cookie Compliance)', 'keyword' => 'hu-banner' ),
2030 + 'gdpr-cookie-compliance' => array( 'label' => 'GDPR Cookie Compliance (Moove)', 'keyword' => 'gdpr-cookie-compliance' ),
2031 + 'app.termly.io' => array( 'label' => 'Termly', 'keyword' => 'termly' ),
2032 + 'usercentrics.eu' => array( 'label' => 'Usercentrics', 'keyword' => 'usercentrics' ),
2033 + 'cdn.iubenda.com' => array( 'label' => 'Iubenda', 'keyword' => 'iubenda' ),
2034 + 'cdn.cookielaw.org' => array( 'label' => 'OneTrust', 'keyword' => 'cookielaw' ),
2035 + 'borlabs-cookie' => array( 'label' => 'Borlabs Cookie', 'keyword' => 'borlabs' ),
2036 + 'real-cookie-banner' => array( 'label' => 'Real Cookie Banner', 'keyword' => 'real-cookie-banner' ),
2037 + 'surecookie' => array( 'label' => 'SureCookie', 'keyword' => 'surecookie' ),
2038 + );
2039 +
2040 + /**
2041 + * "Label (keyword)" for every built-in consent manager, for the admin.
2042 + *
2043 + * Reads the built-in list, not the filtered floor: the admin describes
2044 + * what ships, and a site that trimmed the floor in code knows it did.
2045 + *
2046 + * @return string[]
2047 + */
2048 + public static function consent_manager_labels(): array {
2049 + $out = array();
2050 + foreach ( self::CONSENT_MANAGER_FLOOR as $token ) {
2051 + $name = self::CONSENT_MANAGER_NAMES[ $token ] ?? array(
2052 + 'label' => $token,
2053 + 'keyword' => $token,
2054 + );
2055 + $out[] = $name['label'] . ' (' . $name['keyword'] . ')';
2056 + }
2057 + return $out;
2058 + }
2059 +
2060 + /**
2061 + * Per-request memo for exclusion_floor(). Null = not resolved.
2062 + *
2063 + * @var string[]|null
2064 + */
2065 + private static $exclusion_floor = null;
2066 +
2067 + /**
2068 + * The built-in exclusion floor, after the site has had its say.
2069 + *
2070 + * @return string[]
2071 + */
2072 + private static function exclusion_floor(): array {
2073 + if ( null === self::$exclusion_floor ) {
2074 + /**
2075 + * Scripts that are never deferred or delayed, whatever the
2076 + * user's exclusion list holds. Each entry is an exact script
2077 + * handle or a case-insensitive URL substring.
2078 + *
2079 + * Return the array minus a token to let Delay JS postpone that
2080 + * consent manager on purpose; add one to protect another script.
2081 + *
2082 + * @param string[] $floor Built-in floor.
2083 + */
2084 + $floor = apply_filters( 'xspeed_js_exclusion_floor', self::CONSENT_MANAGER_FLOOR );
2085 + self::$exclusion_floor = array_values(
2086 + array_filter( array_map( 'strval', (array) $floor ), static fn( $t ) => '' !== $t )
2087 + );
2088 + }
2089 + return self::$exclusion_floor;
2090 + }
2091 +
2092 + /**
2093 + * @param string $handle Script handle ('' on the buffer sweep
2094 + * when no id survived).
2095 + * @param string $src Script URL.
2096 + * @param bool $named_lifts_floor Delay paths only: a delay_js_targets
2097 + * entry that NAMES the consent manager
2098 + * passes the floor (see
2099 + * user_named_consent_manager()). Typing a
2100 + * consent manager's name into an
2101 + * allow-list is the site owner taking the
2102 + * consent-timing decision back — GDPR is
2103 + * theirs to weigh, not ours; the floor
2104 + * only exists so Delay JS can't hide a
2105 + * banner NOBODY pointed at. Their own
2106 + * exclusion list, ALWAYS_EXCLUDED_HANDLES
2107 + * and our beacons still win: on a
2108 + * conflict between the user's two lists,
2109 + * protection beats postponement.
2110 + */
2111 + private static function is_excluded_script( string $handle, string $src, bool $named_lifts_floor = false ): bool {
289 2112 if ( in_array( $handle, self::ALWAYS_EXCLUDED_HANDLES, true ) ) {
290 2113 return true;
291 2114 }
2115 + // Never defer or delay our own scripts. The fold and RUM beacons
2116 + // measure the FIRST paint — delayed to first interaction they
2117 + // measure a scrolled page or nothing, so fold quorum never fills
2118 + // and full CSS deferral never licenses. Found live: delay_js with
2119 + // empty targets delayed the fold beacon itself, and the site sat
2120 + // at zero fold reports for hours while its stylesheets stayed
2121 + // render-blocking. Prefix, not a handle list, so a Pro module's
2122 + // beacon added later cannot re-open the hole.
2123 + if ( 0 === strpos( $handle, 'xspeed-' ) ) {
2124 + return true;
2125 + }
2126 + // Ahead of the user list, and ahead of the empty-list early return
2127 + // below: an install that saved the Minify panel before this shipped
2128 + // has a stored list that knows nothing about consent managers, and
2129 + // one that cleared the textarea has no list at all. Neither may
2130 + // hide the banner. (#275)
2131 + foreach ( self::exclusion_floor() as $needle ) {
2132 + if ( self::target_matches( $needle, $handle, $src ) ) {
2133 + // `continue`, not `break`: a second floor token matching the
2134 + // same tag has to be named too, or a filter-added token
2135 + // would be lifted by an entry that names only the first.
2136 + if ( $named_lifts_floor && self::user_named_consent_manager( $needle, $handle, $src ) ) {
2137 + continue;
2138 + }
2139 + return true;
2140 + }
2141 + }
292 2142 $opts = self::opts();
293 2143 $excluded = is_array( $opts['defer_js_excluded'] ?? null ) ? $opts['defer_js_excluded'] : array();
294 2144 if ( empty( $excluded ) ) {
295 2145 return false;
@@ -294,13 +2144,111 @@
294 2144 if ( empty( $excluded ) ) {
295 2145 return false;
296 2146 }
297 2147 foreach ( $excluded as $needle ) {
2148 + // Matched against the pre-minify URL too: an exclusion that
2149 + // stops matching is worse than a delay target that does — the
2150 + // script the user explicitly protected gets deferred anyway.
2151 + if ( self::target_matches( (string) $needle, $handle, $src ) ) {
2152 + return true;
2153 + }
2154 + }
2155 + return false;
2156 + }
2157 +
2158 + /**
2159 + * Include-list targeting for delay (issue #36): when delay_js_targets
2160 + * is non-empty, ONLY matching scripts are delayed — a heavy
2161 + * third-party embed can be postponed without delaying the whole
2162 + * page's JS. Empty targets = historical behavior (delay everything
2163 + * minus exclusions). Same matching semantics as the exclusion list:
2164 + * exact handle match OR case-insensitive URL substring.
2165 + */
2166 + /**
2167 + * Whether the user's delay_js_targets list matches this haystack.
2168 + *
2169 + * The inline-snippet pass needs the target list WITHOUT
2170 + * is_delay_target()'s empty-list-means-everything default — an inline
2171 + * body is only ever delayed on a positive match.
2172 + *
2173 + * @param string $haystack Script body (or URL) to match fragments against.
2174 + */
2175 + private static function matches_user_targets( string $haystack ): bool {
2176 + $opts = self::opts();
2177 + $targets = is_array( $opts['delay_js_targets'] ?? null ) ? $opts['delay_js_targets'] : array();
2178 + foreach ( $targets as $needle ) {
298 2179 $needle = (string) $needle;
2180 + if ( '' !== $needle && false !== stripos( $haystack, $needle ) ) {
2181 + return true;
2182 + }
2183 + }
2184 + return false;
2185 + }
2186 +
2187 + /**
2188 + * Whether the user EXPLICITLY named this script in delay_js_targets.
2189 + *
2190 + * Unlike is_delay_target() this never treats an empty list as
2191 + * everything and never falls back to the vendor list — it answers
2192 + * only "did the user deliberately point at this handle/URL?", which
2193 + * is what lets an explicit entry override the inline-bound guard.
2194 + *
2195 + * @param string $handle Script handle.
2196 + * @param string $src Script URL.
2197 + */
2198 + private static function is_user_named_target( string $handle, string $src ): bool {
2199 + $opts = self::opts();
2200 + $targets = is_array( $opts['delay_js_targets'] ?? null ) ? $opts['delay_js_targets'] : array();
2201 + foreach ( $targets as $needle ) {
2202 + $needle = (string) $needle;
2203 + if ( '' !== $needle && self::target_matches( $needle, $handle, $src ) ) {
2204 + return true;
2205 + }
2206 + }
2207 + return false;
2208 + }
2209 +
2210 + /**
2211 + * Whether a delay_js_targets entry NAMES the consent manager whose floor
2212 + * token matched this tag, and so lifts the floor for it.
2213 + *
2214 + * is_user_named_target() is not enough here: it asks whether any entry
2215 + * matches the tag, and a delay target is a URL substring. `/plugins/`,
2216 + * `.js`, `min.js`, `frontend` or the site's own host each match every
2217 + * consent banner on the page, so one broad entry switched the floor off
2218 + * for all of them and brought #275 back. An entry names the vendor when
2219 + * it is the exact handle, or when it contains the vendor's keyword (or
2220 + * its floor token) and still matches the tag, so `notificationx` and
2221 + * `/plugins/notificationx/` lift NotificationX, `termly` cannot lift
2222 + * Cookiebot, and `/plugins/` lifts nothing.
2223 + *
2224 + * A token added through `xspeed_js_exclusion_floor` has no keyword, so
2225 + * only an entry containing that token, or the exact handle, names it.
2226 + *
2227 + * @param string $floor_token The floor entry that matched this tag.
2228 + * @param string $handle Script handle ('' when unknown).
2229 + * @param string $src Script URL, or the body on the inline pass.
2230 + */
2231 + private static function user_named_consent_manager( string $floor_token, string $handle, string $src ): bool {
2232 + $opts = self::opts();
2233 + $targets = is_array( $opts['delay_js_targets'] ?? null ) ? $opts['delay_js_targets'] : array();
2234 + $names = array( $floor_token );
2235 + if ( isset( self::CONSENT_MANAGER_NAMES[ $floor_token ] ) ) {
2236 + $names[] = self::CONSENT_MANAGER_NAMES[ $floor_token ]['keyword'];
2237 + }
2238 + foreach ( $targets as $needle ) {
2239 + $needle = trim( (string) $needle );
299 2240 if ( '' === $needle ) {
300 2241 continue;
301 2242 }
302 - if ( $handle === $needle || false !== stripos( $src, $needle ) ) {
2243 + $names_it = '' !== $handle && $handle === $needle;
2244 + foreach ( $names as $name ) {
2245 + if ( false !== stripos( $needle, $name ) ) {
2246 + $names_it = true;
2247 + break;
2248 + }
2249 + }
2250 + if ( $names_it && self::target_matches( $needle, $handle, $src ) ) {
303 2251 return true;
304 2252 }
305 2253 }
306 2254 return false;
@@ -305,8 +2253,207 @@
305 2253 }
306 2254 return false;
307 2255 }
308 2256
2257 + /** Both toggles on: delay_js and its carry-the-inline-snippets mode. */
2258 + private static function smart_delay_enabled(): bool {
2259 + $opts = self::opts();
2260 + return ! empty( $opts['delay_js'] ) && ! empty( $opts['delay_js_smart'] );
2261 + }
2262 +
2263 + /**
2264 + * Would Smart Delay postpone this handle's tag?
2265 + *
2266 + * The snippet-parking filter runs when WordPress prints a handle's
2267 + * `before` snippet — BEFORE script_loader_tag sees the tag itself — so
2268 + * the decision cannot be read back from what happened to the tag; both
2269 + * sides evaluate this same predicate. It mirrors the handle/src checks
2270 + * of delay_script_tag() only: the tag-level outs there (an optimizer
2271 + * opt-out attribute, a non-executable type) are invisible here, so a
2272 + * tag that keeps itself eager through one of those can still have its
2273 + * snippets parked. That parks an init until first interaction rather
2274 + * than throwing, and Smart Delay is opt-in — acceptable, and documented
2275 + * on the setting.
2276 + */
2277 + private static function smart_delays_handle( string $handle ): bool {
2278 + if ( '' === $handle ) {
2279 + return false;
2280 + }
2281 + $src = self::original_src( $handle );
2282 + if ( self::is_excluded_script( $handle, $src, true ) ) {
2283 + return false;
2284 + }
2285 + return self::is_delay_target( $handle, $src );
2286 + }
2287 +
2288 + /**
2289 + * Park a delayed handle's own before/after snippet, in Smart Delay mode.
2290 + *
2291 + * Runs on `wp_inline_script_attributes`, which fires for every inline
2292 + * script WordPress prints itself — so it works on pages the HTML buffer
2293 + * never filters (a BYPASS route like /cart), where the handle's tag is
2294 + * still delayed by script_loader_tag. `-js-extra` stays eager on
2295 + * purpose: it is data assignments, harmless early and sometimes read by
2296 + * eager code.
2297 + *
2298 + * @param mixed $attributes Inline script attributes.
2299 + * @param string $javascript The snippet body.
2300 + * @return mixed
2301 + */
2302 + public static function park_smart_inline( $attributes, $javascript = '' ) {
2303 + if ( ! is_array( $attributes ) || ! self::smart_delay_enabled() || self::skip_in_non_frontend_context() ) {
2304 + return $attributes;
2305 + }
2306 + $id = isset( $attributes['id'] ) ? (string) $attributes['id'] : '';
2307 + if ( ! preg_match( '#^(.+)-js-(?:before|after)$#', $id, $m ) ) {
2308 + return $attributes;
2309 + }
2310 + if ( ! self::smart_delays_handle( $m[1] ) ) {
2311 + return $attributes;
2312 + }
2313 + $type = isset( $attributes['type'] ) ? (string) $attributes['type'] : '';
2314 + if ( in_array( $type, self::NON_EXECUTABLE_TYPES, true ) ) {
2315 + return $attributes; // data, or parked by someone else on purpose.
2316 + }
2317 + // A delayed document.write replays after the document has closed
2318 + // and replaces the page. Same rule as delay_inline_snippets().
2319 + if ( false !== stripos( (string) $javascript, 'document.write' ) ) {
2320 + return $attributes;
2321 + }
2322 + if ( '' !== $type && ! in_array( $type, self::DEFAULT_JS_TYPES, true ) ) {
2323 + $stash = (string) preg_replace( '#[^a-z0-9/+.\-]#', '', $type );
2324 + if ( '' !== $stash ) {
2325 + $attributes['data-xs-type'] = $stash;
2326 + }
2327 + }
2328 + $attributes['type'] = 'text/xspeed-delayed';
2329 + $attributes['data-xs-delay'] = '1';
2330 + return $attributes;
2331 + }
2332 +
2333 + private static function is_delay_target( string $handle, string $src ): bool {
2334 + $opts = self::opts();
2335 + $targets = is_array( $opts['delay_js_targets'] ?? null ) ? $opts['delay_js_targets'] : array();
2336 + $targets = array_filter( array_map( 'strval', $targets ), static fn( $t ) => '' !== $t );
2337 + if ( empty( $targets ) ) {
2338 + return true;
2339 + }
2340 + foreach ( $targets as $needle ) {
2341 + if ( self::target_matches( $needle, $handle, $src ) ) {
2342 + return true;
2343 + }
2344 + }
2345 + // The user's list is an ALLOW-list, so a target they never thought to
2346 + // add is not delayed — and the scripts worth delaying are third-party
2347 + // tags nobody enumerates by hand. Falling back to the built-in vendor
2348 + // list means a site that lists one heavy embed still gets the obvious
2349 + // analytics and widget tags postponed, instead of silently keeping
2350 + // them on the main thread. (A user who wants one of these to run
2351 + // early excludes it; the exclusion list is checked before this.)
2352 + return self::matches_known_third_party( $src );
2353 + }
2354 +
2355 + /**
2356 + * Whether a URL belongs to a third-party tag that is safe to postpone.
2357 + *
2358 + * These are analytics, tag managers, chat widgets, review embeds, session
2359 + * recorders and error trackers: scripts that never paint anything above
2360 + * the fold and that no first-party code holds a synchronous reference to.
2361 + * They are also the scripts that dominate a real page's blocking time —
2362 + * on embedpress.com one chat widget alone accounted for ~450ms of TBT and
2363 + * a 22-point score swing between runs, purely on whether it happened to
2364 + * arrive inside the measurement window.
2365 + *
2366 + * Matched on URL only, never on handle: these tags are printed straight
2367 + * into wp_head / wp_footer by their vendors' snippets and usually have no
2368 + * WordPress handle at all. Host fragments rather than whole domains, so a
2369 + * regional or versioned CDN path still matches.
2370 + *
2371 + * Deliberately NOT here: anything from the site's own origin, jQuery, or
2372 + * any wp-* core script. Those carry inline consumers, and delaying them
2373 + * is what breaks pages — see inline_bound_handles().
2374 + */
2375 + private const KNOWN_THIRD_PARTY_SRC = array(
2376 + // Tag managers and analytics.
2377 + 'googletagmanager.com',
2378 + 'google-analytics.com',
2379 + 'analytics.google.com',
2380 + '/gtag/js',
2381 + 'gtm4wp',
2382 + 'plausible.io',
2383 + 'matomo',
2384 + 'segment.com/analytics.js',
2385 + 'stats.wp.com',
2386 + // Advertising and conversion pixels.
2387 + 'connect.facebook.net',
2388 + 'fbevents.js',
2389 + 'ads-twitter.com',
2390 + 'snap.licdn.com',
2391 + 'analytics.tiktok.com',
2392 + 'googleadservices.com',
2393 + 'doubleclick.net',
2394 + // Session recording and heatmaps.
2395 + 'hotjar.com',
2396 + 'clarity.ms',
2397 + 'mouseflow.com',
2398 + 'fullstory.com',
2399 + 'luckyorange',
2400 + // Chat and support widgets.
2401 + 'client.crisp.chat',
2402 + 'widget.intercom.io',
2403 + 'js.driftt.com',
2404 + 'tawk.to',
2405 + 'livechatinc.com',
2406 + 'zdassets.com',
2407 + 'helpscout.net',
2408 + // Reviews, social proof and marketing.
2409 + 'tp.widget.bootstrap',
2410 + 'trustpilot.com',
2411 + 'static.klaviyo.com',
2412 + 'js.hs-scripts.com',
2413 + 'list-manage.com',
2414 + 'sumo.com',
2415 + // Error and performance monitoring.
2416 + 'sentry-cdn.com',
2417 + 'browser.sentry',
2418 + 'bugsnag.com',
2419 + 'newrelic.com',
2420 + );
2421 +
2422 + /**
2423 + * Match a script URL against the built-in third-party list.
2424 + *
2425 + * @param string $src Script source URL.
2426 + */
2427 + private static function matches_known_third_party( string $src ): bool {
2428 + if ( '' === $src ) {
2429 + return false;
2430 + }
2431 +
2432 + $known = self::KNOWN_THIRD_PARTY_SRC;
2433 +
2434 + /**
2435 + * URL fragments the delay pass treats as safe-to-postpone third-party
2436 + * tags when the user's target list does not match.
2437 + *
2438 + * Append a vendor this list does not know yet, or remove one the site
2439 + * genuinely needs early. Entries are case-insensitive substrings of
2440 + * the script URL.
2441 + *
2442 + * @param string[] $known Built-in fragments.
2443 + * @param string $src The script URL being tested.
2444 + */
2445 + $known = (array) apply_filters( 'xspeed_delay_known_third_party', $known, $src );
2446 +
2447 + foreach ( $known as $needle ) {
2448 + $needle = (string) $needle;
2449 + if ( '' !== $needle && false !== stripos( $src, $needle ) ) {
2450 + return true;
2451 + }
2452 + }
2453 + return false;
2454 + }
2455 +
309 2456 private static function opts(): array {
310 2457 if ( null === self::$opts ) {
311 2458 self::$opts = Settings_Manager::get( 'minify' );
312 2459 }
@@ -317,7 +2464,285 @@
317 2464 * Test-only — clear cached opts + bootstrap-printed flag.
318 2465 */
319 2466 public static function reset_state(): void {
320 2467 self::$opts = null;
2468 + self::$uploads_base = null;
321 2469 self::$delay_bootstrap_printed = false;
2470 + self::$js_measured_layout = null;
2471 + self::$has_critical_css = null;
2472 + self::$exclusion_floor = null;
2473 + self::$inline_bound_handles = null;
2474 + self::$pristine_tag = array();
2475 + self::$our_late_attrs = array();
2476 + }
2477 +
2478 + /**
2479 + * Per-request memo for inline_bound_handles(). Null = not resolved.
2480 + *
2481 + * @var array<string,true>|null
2482 + */
2483 + private static $inline_bound_handles = null;
2484 +
2485 + /**
2486 + * Handles that cannot be deferred because inline code depends on them.
2487 + *
2488 + * #234 fixed the case where a handle carries its OWN inline block: the
2489 + * tag WordPress hands the filter is `before_inline + external +
2490 + * after_inline`, so defer goes on the external <script> and order holds.
2491 + * That leaves the cross-handle case, which is the one that actually
2492 + * breaks sites: `wp_add_inline_script( 'foo', … )` prints a bare inline
2493 + * block that runs at parse time and calls into whatever `foo` — or any
2494 + * of foo's DEPENDENCIES — defined. Inline scripts can never be deferred
2495 + * (the HTML spec ignores the attribute), so deferring anything they read
2496 + * from inverts the order WordPress guarantees and throws on a global
2497 + * that is not there yet.
2498 + *
2499 + * jQuery is the canonical victim: one `wp_add_inline_script( 'jquery',
2500 + * 'jQuery(function($){…})' )` anywhere on the page makes `jquery-core`
2501 + * undeferrable, and every hand-maintained exclusion list in the wild
2502 + * exists to say so. The registry already knows it, so read it instead of
2503 + * asking the user.
2504 + *
2505 + * Walks each handle carrying `after`/`before` inline data and marks the
2506 + * handle plus its transitive dependency chain. Cycles are guarded by the
2507 + * seen-map, so a self- or mutually-referential deps array terminates.
2508 + *
2509 + * Pure aside from the global registry read; memoised per request and
2510 + * cleared by reset_state().
2511 + *
2512 + * @return array<string,true> Handle => true, for O(1) lookup.
2513 + */
2514 + public static function inline_bound_handles(): array {
2515 + if ( null !== self::$inline_bound_handles ) {
2516 + return self::$inline_bound_handles;
2517 + }
2518 +
2519 + $bound = array();
2520 + if ( function_exists( 'wp_scripts' ) ) {
2521 + $scripts = wp_scripts();
2522 + if ( $scripts instanceof \WP_Scripts ) {
2523 + foreach ( array_keys( (array) $scripts->registered ) as $handle ) {
2524 + $handle = (string) $handle;
2525 + if ( ! self::handle_carries_inline( $scripts, $handle ) ) {
2526 + continue;
2527 + }
2528 + self::mark_with_deps( $scripts, $handle, $bound );
2529 + }
2530 + }
2531 + }
2532 +
2533 + /**
2534 + * Handles auto-excluded from defer because inline code reads them.
2535 + *
2536 + * Return a handle => true map. Add an entry to protect a script whose
2537 + * inline consumer this cannot see (one printed directly by a theme
2538 + * rather than through wp_add_inline_script), or remove one to defer a
2539 + * handle whose inline block is known not to touch it.
2540 + *
2541 + * @param array<string,true> $bound Detected handles.
2542 + */
2543 + $bound = (array) apply_filters( 'xspeed_defer_inline_bound_handles', $bound );
2544 +
2545 + self::$inline_bound_handles = $bound;
2546 +
2547 + return self::$inline_bound_handles;
2548 + }
2549 +
2550 + /**
2551 + * Whether a handle must be kept out of a combined bundle.
2552 + *
2553 + * Combining re-homes a script's code under a different handle, so every
2554 + * protection keyed to the ORIGINAL handle or URL stops matching: the
2555 + * user's `defer_js_excluded` entry, and the inline-bound set above. The
2556 + * combiner already refuses a handle carrying its own inline data, which
2557 + * is why the gap is invisible until you look for it — a DEPENDENCY of an
2558 + * inline consumer carries none of its own, so `jquery-core` lands in the
2559 + * bundle while the exclusion list still reads as though it were honoured.
2560 + *
2561 + * Returning true here is enough on its own: the combiner drops any
2562 + * dependent of an uncombinable handle transitively, so the whole chain
2563 + * stays in the queue where WordPress prints it in the right order.
2564 + *
2565 + * @param string $handle Script handle.
2566 + * @param string $src Registered source URL.
2567 + */
2568 + public static function is_protected_from_bundling( string $handle, string $src ): bool {
2569 + if ( self::is_excluded_script( $handle, $src ) ) {
2570 + return true;
2571 + }
2572 + return isset( self::inline_bound_handles()[ $handle ] );
2573 + }
2574 +
2575 + /**
2576 + * Whether a handle has inline JS attached in either position.
2577 + *
2578 + * `get_data()` returns the raw value, which is an array of code chunks
2579 + * for `after` and a string for `before`; both are falsy when absent, and
2580 + * an empty chunk array must not count as inline code.
2581 + *
2582 + * @param \WP_Scripts $scripts Registry.
2583 + * @param string $handle Handle to inspect.
2584 + */
2585 + private static function handle_carries_inline( \WP_Scripts $scripts, string $handle ): bool {
2586 + foreach ( array( 'after', 'before' ) as $position ) {
2587 + $data = $scripts->get_data( $handle, $position );
2588 + if ( is_array( $data ) ) {
2589 + foreach ( $data as $chunk ) {
2590 + if ( '' !== trim( (string) $chunk ) ) {
2591 + return true;
2592 + }
2593 + }
2594 + continue;
2595 + }
2596 + if ( '' !== trim( (string) $data ) ) {
2597 + return true;
2598 + }
2599 + }
2600 + return false;
2601 + }
2602 +
2603 + /**
2604 + * Mark a handle and everything it depends on, transitively.
2605 + *
2606 + * @param \WP_Scripts $scripts Registry.
2607 + * @param string $handle Handle to mark.
2608 + * @param array<string,true> $seen Accumulator, by reference.
2609 + */
2610 + private static function mark_with_deps( \WP_Scripts $scripts, string $handle, array &$seen ): void {
2611 + if ( isset( $seen[ $handle ] ) ) {
2612 + return;
2613 + }
2614 + $seen[ $handle ] = true;
2615 + if ( ! isset( $scripts->registered[ $handle ]->deps ) ) {
2616 + return;
2617 + }
2618 + foreach ( (array) $scripts->registered[ $handle ]->deps as $dep ) {
2619 + self::mark_with_deps( $scripts, (string) $dep, $seen );
2620 + }
2621 + }
2622 +
2623 + /**
2624 + * Per-request memo for page_has_js_measured_layout(). Null = not resolved.
2625 + *
2626 + * @var bool|null
2627 + */
2628 + private static $js_measured_layout = null;
2629 +
2630 + /**
2631 + * Per-request memo for page_has_critical_css(). Null = not resolved.
2632 + *
2633 + * @var bool|null
2634 + */
2635 + private static $has_critical_css = null;
2636 +
2637 + /**
2638 + * Does something inline critical CSS for the page being served?
2639 + *
2640 + * Free generates none, so the answer comes from the filter: an extension
2641 + * that inlines critical CSS for this page returns true, and a site whose
2642 + * theme ships its own can too. Resolved once per request, because every
2643 + * stylesheet tag asks.
2644 + */
2645 + public static function page_has_critical_css(): bool {
2646 + if ( null === self::$has_critical_css ) {
2647 + /**
2648 + * Whether the page being served has critical CSS inlined in its head.
2649 + *
2650 + * Async CSS defers stylesheets only when this is true; without
2651 + * critical CSS it leaves them render-blocking, because deferring
2652 + * them makes the page paint unstyled and shift. Return true when
2653 + * something inlines critical CSS for this page, or to keep deferring
2654 + * without it.
2655 + *
2656 + * @param bool $has_critical_css Default false.
2657 + */
2658 + self::$has_critical_css = (bool) apply_filters( 'xspeed_async_css_page_has_critical_css', false );
2659 + }
2660 + return self::$has_critical_css;
2661 + }
2662 +
2663 + /**
2664 + * Scripts that lay out the page by measuring the DOM.
2665 + *
2666 + * Each of these reads element sizes and then writes positions. If the CSS
2667 + * that sizes those elements has not applied when the script runs, it
2668 + * measures the wrong values and commits a broken layout that no later
2669 + * stylesheet can correct.
2670 + *
2671 + * Matched as a substring of the registered handle, so a plugin shipping
2672 + * `acme-masonry` or `masonry-init` is covered without naming it here.
2673 + *
2674 + * @return string[]
2675 + */
2676 + private static function js_layout_script_markers(): array {
2677 + return array(
2678 + 'masonry',
2679 + 'isotope',
2680 + 'packery',
2681 + 'salvattore',
2682 + 'justified-gallery',
2683 + 'slick',
2684 + 'splide',
2685 + 'swiper',
2686 + 'flickity',
2687 + 'owl-carousel',
2688 + 'matchheight',
2689 + );
2690 + }
2691 +
2692 + /**
2693 + * True when a script that measures the DOM to build a layout is enqueued
2694 + * for this request.
2695 + *
2696 + * Reads the enqueue registry rather than the finished HTML, because this
2697 + * runs on `style_loader_tag` — while the head is being printed, before any
2698 + * body markup exists to scan. Both the queue and each queued handle's
2699 + * dependencies are checked: core registers `masonry` as a DEPENDENCY of a
2700 + * plugin's init script, so it is frequently absent from the queue itself.
2701 + *
2702 + * Pure aside from the global registry read; the result is memoised per
2703 + * request and cleared by reset_state().
2704 + */
2705 + public static function page_has_js_measured_layout(): bool {
2706 + if ( null !== self::$js_measured_layout ) {
2707 + return self::$js_measured_layout;
2708 + }
2709 +
2710 + $found = false;
2711 + if ( function_exists( 'wp_scripts' ) ) {
2712 + $scripts = wp_scripts();
2713 + if ( $scripts instanceof \WP_Scripts ) {
2714 + $handles = (array) $scripts->queue;
2715 + // Pull in dependencies — `masonry` usually arrives that way.
2716 + foreach ( (array) $scripts->queue as $queued ) {
2717 + if ( isset( $scripts->registered[ $queued ]->deps ) ) {
2718 + $handles = array_merge( $handles, (array) $scripts->registered[ $queued ]->deps );
2719 + }
2720 + }
2721 + $markers = self::js_layout_script_markers();
2722 + foreach ( $handles as $handle ) {
2723 + $handle = strtolower( (string) $handle );
2724 + foreach ( $markers as $marker ) {
2725 + if ( false !== strpos( $handle, $marker ) ) {
2726 + $found = true;
2727 + break 2;
2728 + }
2729 + }
2730 + }
2731 + }
2732 + }
2733 +
2734 + /**
2735 + * Whether this request renders a JS-measured layout, making async CSS
2736 + * unsafe for the whole page.
2737 + *
2738 + * Return false to defer anyway (a site that ships critical CSS, or one
2739 + * whose grid is pure CSS), or true to protect a library not detected
2740 + * by handle.
2741 + *
2742 + * @param bool $found Whether a measuring script was detected.
2743 + */
2744 + self::$js_measured_layout = (bool) apply_filters( 'xspeed_async_css_js_measured_layout', $found );
2745 +
2746 + return self::$js_measured_layout;
322 2747 }
323 2748 }