I am unable to save Writing Settings. When I click the [Save Changes] button, I’m dumped out to the website. When I go back into the Dashboard and check the Writing Settings (Settings->Writing), no changes were saved.
This is with WordPress 5.5.1. For testing purposes, I’ve disabled all plugins and changed the theme to the Twenty Twenty theme — it has made no difference: I am still unable to save changes to Writing Settings and the behavior is the same (clicking [Save Changes] takes me to website).
Any ideas how to fix this?