I invite you to read the tutorial for more details.
The Oxygen editor (outer editor) loads the page that you want to edit inside an iframe (inner editor).
When the Oxygen editor loads, it send some Ajax requests calling the file wp-admin/admin-ajax.php.
Usually, also other plugins hook to that file during the loading process. Sometimes one or more of those plugins cause conflicts that prevent the editor from loading.
With the free version of FDP, you can prevent some plugins from loading on the outer and inner editor, but not during the Ajax requests. You would need the PRO version to do that.
But you can now use Editor Cleanup For Oxygen. a free add-on of FDP.
After the activation, go to Oxygen => Editor Cleanup.
You will see the three buttons to disable plugins:
- in the outer Oxygen editor
- in the inner Oxygen editor
- during the loading of the Oxygen editor
Usually, you don’t need any plugin in the outer editor and during the loading process.
The inner editor is nothing else than the page that you are editing, but called inside an iframe. In the inner editor disable the same plugins that you would disable on the frontend for that page.
Download Editor Cleanup For Oxygen to speed up the Oxygen editor, and don’t have anymore any conflict with other plugins.
You can install the plugin also from your WordPress backend.
Search “Editor Cleanup For Oxygen” on the page of plugins.