Issue #2626106 by Wim Leers, gceja, thpoul: The image button does not work...

Issue #2626106 by Wim Leers, gceja, thpoul: The image button does not work unless width+height attributes are allowed, even though those are optional

core/modules/ckeditor/js/plugins/drupalimage/plugin.js

@@ -255,7 +255,7 @@
       // the "image" command's CKEditor dialog with a Drupal-native dialog.
       editor.addCommand('editdrupalimage', {
         allowedContent: 'img[alt,!src,width,height,!data-entity-type,!data-entity-uuid]',
-        requiredContent: 'img[alt,src,width,height,data-entity-type,data-entity-uuid]',
+        requiredContent: 'img[alt,src,data-entity-type,data-entity-uuid]',
         modes: {wysiwyg: 1},
         canUndo: true,
         exec: function (editor, data) {