fix: handle all temp user errors by reloading

src/gui/src/initgui.js

@@ -845,10 +845,12 @@ window.initgui = async function(options){
                 window.update_auth_data(data.token, data.user);
                 document.dispatchEvent(new Event("login", { bubbles: true}));
             },
-            error: function (err){
-                UIAlert({
-                    message: html_encode(err.responseText),
-                });
+            error: async (err) => {
+                // The solution to any error that might happen here is to reload the page.
+                // We only try to sign into a temporary user on the first visit, so if it
+                // didn't work reloading the page will produce the login screen.
+                console.log('could not create temporary user', err);
+                window.location.reload();
             }
         });
     }