CKEditor incorrectly resolves links to language pages, but in the /admin/

[donatas]

I have a multi language set up that is working fine for couple of years.

default = Italian
en = English
...

But recently noticed that if I add a link with CKEditors PWLink plugin (like with "Select page") in a rich text field on a non-default language to the language homepage:

/en/

it converts it to the admin language management page link after saving and the links don't work for visitors (and Google indexing too):

/en/admin/setup/languages/en/

Would seem like a bug, but maybe there are ways to hide the admin lang pages from the PWLink?

The rich text field has "Link abstraction", ACF and HTML purifier ON, would not want to turn these off as the website is quite large with a lot of rich text content.

Any ideas where to look to fix this?