Ticket #38492: 38492.1.diff

src/wp-admin/js/customize-controls.js

@@ -4173 +4173 @@
                                 _.find( parsedCandidateUrls, function( parsedCandidateUrl ) {
                                         return ! _.isUndefined( _.find( previewer.allowedUrls, function( allowedUrl ) {
                                                 parsedAllowedUrl.href = allowedUrl;
-                                                if ( urlParser.protocol === parsedAllowedUrl.protocol && urlParser.host === parsedAllowedUrl.host && 0 === parsedAllowedUrl.pathname.indexOf( urlParser.pathname ) ) {
+                                                if ( urlParser.protocol === parsedAllowedUrl.protocol && urlParser.host === parsedAllowedUrl.host && 0 === urlParser.pathname.indexOf( parsedAllowedUrl.pathname.replace( /\/$/, '' ) ) ) {
                                                         result = parsedCandidateUrl.href;
                                                         return true;
                                                 }