Do not redirect to empty URLs on progress page

CHANGELOG.rst

@@ -22,6 +22,7 @@ Fixed
 
 * Fix installation documentation (nginx, uWSGI).
 * Use a set for data checks registry to prevent double entries.
+* Progress page tried to redirect even if the URL is empty.
 
   Removed
 ~~~~~~~

aleksis/core/static/js/progress.js

@@ -47,7 +47,7 @@ function customSuccess(progressBarElement, progressBarMessageElement) {
     $("#result-icon").text("check_circle");
     $("#result-text").text(OPTIONS.success);
     $("#result-box").show();
-    const redirect = "redirect_on_success" in OPTIONS;
+    const redirect = "redirect_on_success" in OPTIONS && OPTIONS.redirect_on_success;
     if (redirect) {
         window.location.replace(OPTIONS.redirect_on_success);
     }