Description of problem:
The declaration of the EDITOR variable in the universal scope makes it persist past uninstallation and reboot, as fish records setting universal variables in a persistent state database for a user profile.
The EDITOR variable should *not* be set as a universal variable so that it can be removed easily.
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. Switch to fish
2. Uninstall nano-default-editor
3. echo $EDITOR
EDITOR is set to /bin/fish
EDITOR is unset
FEDORA-2020-f4c0c2f406 has been submitted as an update to Fedora 33. https://bodhi.fedoraproject.org/updates/FEDORA-2020-f4c0c2f406
Proposed as a Freeze Exception for 33-final by Fedora user ngompa using the blocker tracking app because:
This fixes behavior of the $EDITOR variable for fish shell users to behave as we document it to be.
Discussed during the 2020-10-19 blocker review meeting: 
The decision to classify this bug as an "AcceptedFreezeException (Final)" was made as it is a noticeable issue that cannot be fixed with an update.
FEDORA-2020-f4c0c2f406 has been pushed to the Fedora 33 stable repository.
If problem still persists, please make note of it in this bug report.