Current JabRef 5.* dev on Windows 10 64 bit.

Steps to reproduce:

1. Create group which collect its entry by a keyword (e.g. foobar) and create two entries with such a keyword.
2. Select that group and double click on one of the entries.
3. Remove the foobar keyword from that entry.

Now the problem...

4. The entry disappears from the entry list (because it does not has the keyword for that group anymore).
5. The second entry is selected then and the entry editor window changes and selects the second entry, too.

Technical this make sense. But for the user it does not.
And it is hazardouse because the user does not recognize that the entry editor window now containts data from another entry.

Imagine a group with 10 entries: My eyes are only on the keywords field in the entry editor! I remove the keyword. The window flickers but the keyword comes back to my eyes (because the next entry is selected automaticly). I think there is a bug (because it is the dev version and the buggy JavaFX-GUI with non-standard-behaviour) and try again, and again, and again... So I removed multiple entries from that group without recognizing it.

What I (as a user) would expect:

• The entry editor window still contains the first (by me) selected entry. No matter if the entry is still in the entry list or not.
• Or the entry editor window is closed automaticly when its entry disappears from the current entry list.

Could be relevant for #4564