When I attach a Musescore file, it is sometimes stored as a ZIP file. For example music.mszc is stored as music.zip in the resouces directory. The issue is that it does not open with Musescore but with file explorer. Is there a way to prevent Joplin from renaming attachments?
I think that will fix the issue for new MSCZ files you attach. However those are already attached might have the wrong type and will still be detected as ZIP files. If it's important, you may want to remove them from the note and attach them again.