Fix picture element support for post thumbnail

Author: b1ink0

plugins/webp-uploads/hooks.php

@@ -673,6 +673,9 @@ function webp_uploads_img_tag_update_mime_type( string $original_image, string $
  * @return string The updated HTML markup.
  */
 function webp_uploads_update_featured_image( string $html, int $post_id, int $attachment_id ): string {
+	if ( webp_uploads_is_picture_element_enabled() ) {
+		return webp_uploads_wrap_image_in_picture( $html, 'post_thumbnail_html', $attachment_id );
+	}
 	return webp_uploads_img_tag_update_mime_type( $html, 'post_thumbnail_html', $attachment_id );
 }
 add_filter( 'post_thumbnail_html', 'webp_uploads_update_featured_image', 10, 3 );

plugins/webp-uploads/picture-element.php

@@ -19,7 +19,7 @@
  * @return string The new image tag.
  */
 function webp_uploads_wrap_image_in_picture( string $image, string $context, int $attachment_id ): string {
-	if ( 'the_content' !== $context ) {
+	if ( ! in_array( $context, array( 'the_content', 'post_thumbnail_html', 'widget_block_content' ), true ) ) {
 		return $image;
 	}