When you upgrade Domino 11.0.1 to FP8 CKEditor gets upgraded too.
This is a good thing although it would be very helpful if the release notes said this. HCL have a habit of not mentioning these things.
The video below shows a very simple test database that shows the issue. Ignore the tabs comment in the video – we thought that these were an issue but they are not.
The crux is that CKEditor does not work with Domino 11.01 FP8
We are following up with HCL and will update this post
Note that rolling back from FP8 to a previous FP does not downgrade the CKEditor version. You will need to manually replace the /domino/html/ckeditor folder.
The test application is attached here demo_ckeditor_issue_gnl1