No, I am going to delete my plugins instead.
It’s not that making this particular change and re-testing everything afterwards is difficult. It’s that it’s yet another breaking change made for absolutely no reason, demonstrating that the Discourse team couldn’t care less about backward compatibility and breaking people’s forms and code.
The file extensions I used in this project were the ones the Discourse team told me to use at the time the plugin was written. There’s no sane reason to stop supporting the old extensions, but you’re doing it anyway because the team values making things slightly tidier on their side of things than keeping things working.
The team have messed up priorities and I’ve had enough of it.