Merge pull request #786 from Codeinwp/improve/lcp

add fetch priority for lazyload bypassed images to improve lcp

Author: selul

inc/tag_replacer.php

@@ -331,6 +331,12 @@ public function regular_tag_replace( $new_tag, $original_url, $new_url, $optml_a
 				$new_tag = $is_slashed ? str_replace( 'loading=\"lazy\"', 'loading=\"eager\"', $new_tag ) : str_replace( 'loading="lazy"', 'loading="eager"', $new_tag );
 			}
 		}
+		// If the image is between the first images we add the fetchpriority attribute to improve the LCP.
+		if ( self::$lazyload_skipped_images < Optml_Lazyload_Replacer::get_skip_lazyload_limit() ) {
+			if ( strpos( $new_tag, 'fetchpriority=' ) === false ) {
+				$new_tag = preg_replace( '/<img/im', $is_slashed ? '<img fetchpriority=\"high\"' : '<img fetchpriority="high"', $new_tag );
+			}
+		}
 
 		self::$lazyload_skipped_images ++;
 		return preg_replace( $pattern, $replace, $new_tag );