display a loading screen while users are changing their passwords

customize.dist/translations/messages.js

@@ -614,6 +614,7 @@ define(function () {
     out.settings_changePasswordNewConfirm = "Confirm new password";
     out.settings_changePasswordConfirm = "Are you sure you want to change your password? You will need to log back in on all your devices.";
     out.settings_changePasswordError = "An unexpected error occurred. If you are unable to login or change your password, contact your CryptPad administrators.";
+    out.settings_changePasswordPending = "Your password is being updated. Please do not close or reload this page until the process has completed.";
 
     out.upload_title = "File upload";
     out.upload_modal_title = "File upload options";

www/settings/inner.js

@@ -431,10 +431,16 @@ define([
             UI.confirm(Messages.settings_changePasswordConfirm,
             function (yes) {
                 if (!yes) { return; }
+
+                UI.addLoadingScreen({
+                    hideTips: true,
+                    loadingText: Messages.settings_changePasswordPending,
+                });
                 updateBlock({
                     password: oldPassword,
                     newPassword: newPassword
                 }, function (obj) {
+                    UI.removeLoadingScreen();
                     if (obj && obj.error) {
                         // TODO
                         UI.alert(Messages.settings_changePasswordError);