Introduce new wpl_iframe_src filter to enable filtering arguments to Likes iframes.

projects/plugins/jetpack/changelog/update-likes-add-iframe-filter

@@ -0,0 +1,4 @@
+Significance: minor
+Type: other
+
+Likes: Add a filter to the iframe url to enable future expansion and modularity.

projects/plugins/jetpack/modules/likes.php

@@ -448,6 +448,9 @@ function_exists( '\Activitypub\is_activitypub_request' )
 
 		$title = esc_html__( 'Like or Reblog', 'jetpack' );
 
+		/** This filter is documented in modules/likes/jetpack-likes-master-iframe.php */
+		$src = apply_filters( 'jetpack_likes_iframe_src', $src );
+
 		$html  = "<div class='sharedaddy sd-block sd-like jetpack-likes-widget-wrapper jetpack-likes-widget-unloaded' id='$wrapper' data-src='$src' data-name='$name' data-title='$title'>";
 		$html .= $headline;
 		$html .= "<div class='likes-widget-placeholder post-likes-widget-placeholder' style='height: 55px;'><span class='button'><span>" . esc_html__( 'Like', 'jetpack' ) . '</span></span> <span class="loading">' . esc_html__( 'Loading...', 'jetpack' ) . '</span></div>';

projects/plugins/jetpack/modules/likes/jetpack-likes-master-iframe.php

@@ -34,6 +34,17 @@ function jetpack_likes_master_iframe() {
 		$new_layout
 	);
 
+	/**
+	 * Filters the Likes iframe src, if any parameters need to be overridden or tracked.
+	 *
+	 * @module likes
+	 *
+	 * @since $$next-version$$
+	 *
+	 * @param string URL to https://widgets.wp.com/ with various arguments appended to the get string and fragment.
+	 */
+	$src = apply_filters( 'jetpack_likes_iframe_src', $src );
+
 	if ( $new_layout ) {
 		// The span content is replaced by queuehandler when showOtherGravatars is called.
 		$likers_text = wp_kses( '<span>%d</span>', array( 'span' => array() ) );