"End edition" is not the right phrase
"Edition" means a particular version of something; it doesn't really refer to the process of editing. And "End" isn't really the right verb for a command like that; I think "Stop" is better, or maybe "Finish".
The "End edition" button for the playlist editor should really say something like "Stop editing".
I want to just find ./* -type f -exec sed -i 's/End edition/Stop editing/g' {} +'
, but since that sting is used as a message identifier for translations, I'm not sure if that would cause any trouble.