I came across a weird bug with a title containing a "%" character not converting into a proper slug. So the website editor created the title "Berlenga: a 100% sustainable island" that didn't get turned into a proper slug. It generated the slug exactly as the title. When she went to make changes, Craft threw in a bad request error.
I was able to edit the slug inside the database and she got back access the entry, but I am wondering if there is a way to prevent this from happening again. I'm using the "Slug Equals Title" plugin, which works greatly for localised entries, and I did activate "limitAutoSlugsToAscii". Is there something else I need to do?