Don't take a data: placeholder in a lazy-load attribute as the image URL

inc/manager.php

@@ -698,7 +698,9 @@ public static function parse_images_from_html( $content ) {
 		if ( OPTML_DEBUG ) {
 			do_action( 'optml_log', 'Content to parse images from: ' . $content );
 		}
-		$regex = '/(?:<a[^>]+?href=["|\'](?P<link_url>[^\s]+?)["|\'][^>]*?>\s*)?(?P<img_tag>(?:<noscript\s*>\s*)?<img[^>]*?\s?(?:' . implode( '|', array_merge( [ 'src' ], Optml_Tag_Replacer::possible_src_attributes() ) ) . ')=["\'\\\\]*?(?P<img_url>[' . Optml_Config::$chars . ']{10,}).*?>(?:\s*<\/noscript\s*>)?){1}(?:\s*<\/a>)?/ismu';
+		// A lazy-load attribute (e.g. data-src) holding a data: placeholder is skipped, so the real src is used.
+		// A data: src is still matched: the image then belongs to another lazy-load script.
+		$regex = '/(?:<a[^>]+?href=["|\'](?P<link_url>[^\s]+?)["|\'][^>]*?>\s*)?(?P<img_tag>(?:<noscript\s*>\s*)?<img[^>]*?(?:\ssrc=["\'\\\\]*?|\s?(?:' . implode( '|', array_merge( [ 'src' ], Optml_Tag_Replacer::possible_src_attributes() ) ) . ')=["\'\\\\]*?(?!data:))(?P<img_url>[' . Optml_Config::$chars . ']{10,}).*?>(?:\s*<\/noscript\s*>)?){1}(?:\s*<\/a>)?/ismu';
 
 		if ( preg_match_all( $regex, $content, $images, PREG_OFFSET_CAPTURE ) ) {
 			if ( OPTML_DEBUG ) {

tests/test-dimension-replacement.php

@@ -117,6 +117,17 @@ public function test_existing_attributes_preserved() {
 	}
 
 
+	/**
+	 * A data: placeholder in data-src before src does not stop the real image from being processed.
+	 */
+	public function test_dimensions_injected_when_data_src_placeholder_comes_first() {
+		$html_input = '<img data-src="data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" src="' . self::IMAGE_URL . '" alt="Test image">';
+
+		$result = $this->tag_replacer->process_image_tags( $html_input, $this->extract_images_from_html( $html_input ) );
+
+		$this->assertMatchesRegularExpression( '/width="1920".*height="1080".*data-opt-id=' . $this->tag_replacer->get_id_by_url( self::IMAGE_URL ) . '/', $result );
+	}
+
 	/**
 	 * Helper method to extract images from HTML for testing.
 	 * Uses the actual manager method to ensure correct structure.

tests/test-lazyload.php

@@ -553,4 +553,34 @@ public function test_dam_lazyloading_no_wh_attributes() {
 		$this->assertStringContainsString( $svg, $replaced_content );
 		remove_filter('optml_lazyload_images_skip','__return_zero');
 	}
+
+	/**
+	 * A tag whose data-src holds a data: placeholder is lazy-loaded from its real URL.
+	 */
+	public function test_lazyload_tag_with_data_uri_data_src() {
+		$settings = new Optml_Settings();
+		$settings->update( 'skip_lazyload_images', 0 );
+		// The skip limit is cached in a static on first use, so an earlier test may have cached another value.
+		$skip_limit = new ReflectionProperty( Optml_Lazyload_Replacer::class, 'skip_lazyload_images' );
+		$skip_limit->setAccessible( true );
+		$skip_limit->setValue( null, null );
+		Optml_Tag_Replacer::$lazyload_skipped_images = 0;
+		Optml_Manager::instance()->init();
+
+		$placeholder = 'data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==';
+		$tags        = [
+			'<img data-src="' . $placeholder . '" src="https://example.com/wp-content/uploads/2026/10/photo.jpg" alt="Test" />',
+			'<img data-src="' . $placeholder . '" data-lazy-src="https://example.com/wp-content/uploads/2026/10/photo.jpg" alt="Test" />',
+		];
+
+		foreach ( $tags as $tag ) {
+			$replaced_content = Optml_Manager::instance()->replace_content( $tag );
+
+			$this->assertStringContainsString( 'data-opt-src="https://test123.i.optimole.com/', $replaced_content, $tag );
+			$this->assertStringContainsString( '/https://example.com/wp-content/uploads/2026/10/photo.jpg"', $replaced_content, $tag );
+			$this->assertStringContainsString( 'data-src="' . $placeholder . '"', $replaced_content, $tag );
+		}
+
+		$skip_limit->setValue( null, null );
+	}
 }

tests/test-replacer.php

@@ -850,6 +850,44 @@ public function test_dam_flag_removal() {
 		$this->assertStringContainsString('q:mauto', $replaced_content);
 	}
 
+	/**
+	 * A data: placeholder in a lazy-load attribute before src is not taken as the image URL.
+	 */
+	public function test_parse_images_skips_data_uri_in_lazy_attribute() {
+		$placeholder = 'data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==';
+		$real_src    = 'https://example.com/wp-content/uploads/2026/10/photo.jpg';
+
+		$tags = [
+			'<img data-src="' . $placeholder . '" src="' . $real_src . '" alt="Test" />',
+			"<img data-src='" . $placeholder . "' src='" . $real_src . "' alt='Test' />",
+			'<img data-lazy-src="' . $placeholder . '" alt="Test" src="' . $real_src . '" />',
+			'<img src="' . $real_src . '" data-src="' . $placeholder . '" alt="Test" />',
+			'<img DATA-SRC="DATA:image/gif;base64,R0lGODlh" src="' . $real_src . '" />',
+		];
+
+		foreach ( $tags as $tag ) {
+			$images = Optml_Manager::parse_images_from_html( $tag );
+			$this->assertSame( [ $real_src ], $images['img_url'], $tag );
+			$this->assertSame( [ $tag ], $images['img_tag'], $tag );
+		}
+
+		$placeholder_only = '<img data-src="' . $placeholder . '" alt="Test" />';
+		$this->assertSame( [], Optml_Manager::parse_images_from_html( $placeholder_only ) );
+
+		$placeholder_and_lazy_src = '<img data-src="' . $placeholder . '" data-lazy-src="' . $real_src . '" alt="Test" />';
+		$this->assertSame( [ $real_src ], Optml_Manager::parse_images_from_html( $placeholder_and_lazy_src )['img_url'] );
+	}
+
+	/**
+	 * A data: src is still matched, so an image owned by another lazy-load script is handled as before.
+	 */
+	public function test_parse_images_keeps_data_uri_src() {
+		$tag    = '<img src="data:image/gif;base64,R0lGODdhAQABAPAAAP///wAAACwAAAAAAQABAEACAkQBADs=" data-lazy-src="https://example.com/wp-content/uploads/2026/10/photo.jpg" />';
+		$images = Optml_Manager::parse_images_from_html( $tag );
+
+		$this->assertSame( [ 'data:image/gif' ], $images['img_url'] );
+	}
+
 	/**
 	 * Individual cache tokens are stored as the API returned them, which can be a number.
 	 * The SDK only accepts a string cache buster.