I wonder if I may have broken it with my existing signature? I can’t recall exactly what I did but I got it to use a headline and superscript via a mixture of html and markdown.
A couple days ago I made changes to the signature (probably on iPad) but the changes didn’t stick, so I gave up thinking I’ll have to make that update on desktop instead. But even on iPad (Safari) the signature field is now just a non-interactive rectangle.
Thanks for flagging, @CodeSmile. We’ll look into this issue and some other oddities that have cropped up since the latest update. The investigation is scheduled for next week due to team holidays.