What are your server names listed in Help > Troubleshooting Information?

Thanks for the response! Since I was using exactly the same setup as I had the day before, I don't think the problem was in my settings.

I appreciate the reply, but I've rolled back to 115 using an old copy of my profile. It works, and that's good enough, so you can consider this one closed. My mistake was leaving auto update enabled. I won't do that again!

I'll check back in a year and see whether this bug has been fixed.