diff --git a/resources/mmv/mmv.bootstrap.js b/resources/mmv/mmv.bootstrap.js
index 870033021..18bec3d92 100644
--- a/resources/mmv/mmv.bootstrap.js
+++ b/resources/mmv/mmv.bootstrap.js
@@ -129,10 +129,10 @@
 	/**
 	 * Processes all thumbs found on the page
 	 */
-	MMVB.processThumbs = function () {
+	MMVB.processThumbs = function ( $content ) {
 		var bs = this;
 
-		this.$thumbs = $(
+		this.$thumbs = $content.find(
 			'.gallery .image img, ' +
 			'a.image img, ' +
 			'#file a img, ' +
diff --git a/tests/qunit/mmv/mmv.bootstrap.test.js b/tests/qunit/mmv/mmv.bootstrap.test.js
index 585ba6ab9..6d0d6270c 100644
--- a/tests/qunit/mmv/mmv.bootstrap.test.js
+++ b/tests/qunit/mmv/mmv.bootstrap.test.js
@@ -52,6 +52,8 @@
 	function createBootstrap( viewer ) {
 		var bootstrap = new mw.mmv.MultimediaViewerBootstrap();
 
+		bootstrap.processThumbs( $( '#qunit-fixture' ) );
+
 		// MultimediaViewerBootstrap.ensureEventHandlersAreSetUp() is a weird workaround for gadget bugs.
 		// MediaViewer should work without it, and so should the tests.
 		bootstrap.ensureEventHandlersAreSetUp = $.noop;