Ensure showTrackChangesOnboarding is a boolean

services/web/app/views/project/editor.pug

@@ -108,7 +108,7 @@ block requirejs
 		window.anonymous = #{anonymous};
 		window.maxDocLength = #{maxDocLength};
 		window.trackChangesEnabled = #{trackChangesEnabled};
-		window.showTrackChangesOnboarding = #{showTrackChangesOnboarding};
+		window.showTrackChangesOnboarding = #{!!showTrackChangesOnboarding};
 		window.wikiEnabled = #{!!(settings.apis.wiki && settings.apis.wiki.url)};
 		window.requirejs = {
 			"paths" : {