'Open emails in basic HTML mode' option no longer works. The add-on had been working perfectly for years, but yesterday this option stopped working, and no matter how many times I check and uncheck this option, I'm always sent to the standard Gmail version.

The add-on last updated on October 30, 2022 on my end. I also noticed that Firefox appears to have updated yesterday to version 110.0.1, so it's possible that this is what's causing this issue and this add-on probably needs to update to catch up.