What the hell is going on at ST? Every STM uC I've tried to use in the past few years has had showstopper bugs with loads of very similar complaints online dating back to the release of the part. Bugs that have been in the wild for years and still exist in the current production run.

After burning enough company time chasing bugs through ST's crappy silicon, I've had to just swear them off entirely. We're an Atmel house now. Significantly fewer (zero) problems, and some pretty nifty features like UPDI.