Fix loading bar in SPA

CHANGELOG.rst

@@ -14,6 +14,7 @@ Fixed
 
 * Progress page didn't work properly.
 * About page failed to load for apps with an unknown licence.
+* Loading bar didn't disappear on some pages after loading was finished.
 
 `3.1`_ - 2022-05-30
 -------------------

aleksis/core/frontend/components/LegacyBaseTemplate.vue

@@ -71,7 +71,9 @@ export default {
 
       // Show loader if iframe starts to change its content, even if the $route stays the same
       this.$refs.contentIFrame.contentWindow.onpagehide = () => {
-        this.$root.contentLoading = true;
+        if (this.$root.isLegacyBaseTemplate) {
+          this.$root.contentLoading = true;
+        }
       };
 
       // Write title of iframe to SPA window