What about on the left when you create the item? See https://i.imgur.com/y8ou8jp.png
You can’t edit a custom menu item. You can add a new one and remove the old one.
When I make customs links, it gets even weirder:
What did you enter in the URL field?
What I wrote in the last post; WordPress is changing the URLs of the custom links to be like posts. I figured this might have been an issue with permalinks, but trying to reset my permalinks does nothing to solve this. 🙁
I managed to fix it! Enabling
WP_DEBUG revealed a bunch of errors that pointed to a corrupted database. After running the MySQL Repair utility in cPanel, it started working again. YAY!! ^__^
To anyone who may be interested and/or is encountering the same issue as I was, these are the error messages that occurred after adding the item that tipped me off to the database corruption:
Hope this helps somebody.