diff --git a/resources/src/mediawiki.page.gallery.js b/resources/src/mediawiki.page.gallery.js
index 79937e57065..9448ab8a78e 100644
--- a/resources/src/mediawiki.page.gallery.js
+++ b/resources/src/mediawiki.page.gallery.js
@@ -1,6 +1,8 @@
 /*!
- * Show gallery captions when focused. Copied directly from jquery.mw-jump.js.
- * Also Dynamically resize images to justify them.
+ * Enhance MediaWiki galleries (from the `<gallery>` parser tag).
+ *
+ * - Toggle gallery captions when focused.
+ * - Dynamically resize images to fill horizontal space.
  */
 ( function ( mw, $ ) {
 	var $galleries,
@@ -242,8 +244,9 @@
 				.addClass( 'mw-gallery-packed-overlay' )
 				.removeClass( 'mw-gallery-packed-hover' );
 		} else {
-			// Note use of just "a", not a.image, since we want this to trigger if a link in
-			// the caption receives focus
+			// Note use of just `a`, not `a.image`, since we also want this to trigger if a link
+			// within the caption text receives focus.
+			// This is based on code from the 'jquery.mw-jump' module.
 			$content.find( 'ul.mw-gallery-packed-hover li.gallerybox' ).on( 'focus blur', 'a', function ( e ) {
 				// Confusingly jQuery leaves e.type as focusout for delegated blur events
 				var gettingFocus = e.type !== 'blur' && e.type !== 'focusout';