Hi there @doywil
That could mean there may be duplicate DISALLOW_FILE_EDIT entries in the wp-config.php file that are conflicting.
Or it could be server/database cache interfering.
Or perhaps a conflicting setting in some other security plugin you may have installed.
Please check your wp-config.php file to ensure there are no duplicate entries as above, and clear any/all cache on your server if you can.
If the issue is still there, temporarily deactivate all other plugins and check if the theme/plugin editors are then disabled.
If they are, you’d know one of your active plugins is indeed conflicting.
Please do let us know how you get on wit this and if you still need help. ??
Cheers!
Patrick
