Just to add, this occurs only if the poster's home instance and instance of the post is a mismatch. When I made an edit on a Lemmy.ca instance, it went through fine. It's only after I submitted an edit to a post on Lemmy.world that I was able to reproduce the reported bug.
EDIT: Tested and confirmed it's also an issue with Lemmy.ml, so it's not with Lemmy.world.
The dev mentioned they're working on this. If you haven't already, you may want to enroll in the beta builds since it'll be released there first. And they're pretty stable.
It's made in Canada. But is it a product of Canada?