TranslatePress language Switcher, help needed

I need some help with this. Adding the respective language item as a item to the menu, on the frontend everything is ok (e.g. it shows EN). But within the editor, the menu items (header) appears like this:

instead just showing “EN” on the backend.

I found the following hint from the plugin documentation:
“You need to have data-no-translation on the wrapper with the links or TranslatePress will automatically translate them in a secondary language.”

How to do that?

It is with this overall php snippet mentioned on Custom Language Switcher - TranslatePress