Ticket #39387: miqro-39387.diff

src/wp-includes/media.php

@@ -1069 +1069 @@
 
         $image_basename = wp_basename( $image_meta['file'] );
 
+        /**
+         * Filters the on/off behavior of responsive images when a GIF is used.
+         *
+         * @since 4.8.0
+         *
+         * @param bool $make_gifs_responsive Set this to true if you want all GIF images to have responsive srcset.
+         */
+        $make_gifs_responsive = apply_filters( 'wp_calculate_image_srcset_gif', false );
+
         /*
          * WordPress flattens animated GIFs into one frame when generating intermediate sizes.
          * To avoid hiding animation in user content, if src is a full size GIF, a srcset attribute is not generated.
          * If src is an intermediate size GIF, the full size is excluded from srcset to keep a flattened GIF from becoming animated.
          */
-        if ( ! isset( $image_sizes['thumbnail']['mime-type'] ) || 'image/gif' !== $image_sizes['thumbnail']['mime-type'] ) {
+        if ( $make_gifs_responsive || ! isset( $image_sizes['thumbnail']['mime-type'] ) || 'image/gif' !== $image_sizes['thumbnail']['mime-type'] ) {
                 $image_sizes[] = array(
                         'width'  => $image_meta['width'],
                         'height' => $image_meta['height'],