fix: add updates same as PR: django-cms#7599

Code borrowed from:
django-cms#7599
Also, based on on the ticket and work of django-cms#7460

Co-Authored-By: Petr Klus <petr@klus.co.uk>
Co-Authored-By: Fabian Braun <fsbraun@gmx.de>

cms/static/cms/js/modules/cms.structureboard.js

@@ -8,7 +8,7 @@ import Plugin from './cms.plugins';
 import { getPlaceholderIds } from './cms.toolbar';
 import Clipboard from './cms.clipboard';
 import URI from 'urijs';
-import DiffDOM from 'diff-dom';
+import { DiffDOM } from 'diff-dom';
 import PreventParentScroll from 'prevent-parent-scroll';
 import { find, findIndex, once, remove, compact, isEqual, zip, every } from 'lodash';
 import ls from 'local-storage';

cms/tests/frontend/karma.conf.js

@@ -7,7 +7,7 @@
 'use strict';
 
 process.env.NODE_ENV = 'test';
-
+process.env.CHROME_BIN = require('puppeteer').executablePath();
 var baseConf = require('./base.conf');
 var path = require('path');
 var fs = require('fs');
@@ -57,7 +57,7 @@ module.exports = function (config) {
     };
 
     var browsers = {
-        PhantomJS: 'used for local testing'
+        ChromeHeadlessCI: 'used for local testing'
     };
 
     var settings = {
@@ -66,7 +66,7 @@ module.exports = function (config) {
 
         // frameworks to use
         // available frameworks: https://npmjs.org/browse/keyword/karma-adapter
-        frameworks: ['jasmine', 'fixture', 'phantomjs-shim'],
+        frameworks: ['jasmine', 'fixture'],
 
         // list of files / patterns to load in the browser
         files: [
@@ -148,6 +148,14 @@ module.exports = function (config) {
         // start these browsers
         browsers: Object.keys(browsers),
 
+        customLaunchers: {
+            ChromeHeadlessCI: {
+                base: 'ChromeHeadless',
+                flags: ['--window-size=1280,1080']
+            }
+        },
+
+
         concurrency: Infinity,
 
         // we need at least 2 minutes because things are a bit slow