re. penpot : is it possible to comment on a public prototype ?
If you're not logged in, you have the option of leaving a comment, but it doesn't work. Pressing "Send" in the comment box results in a message that says "There was an error." There was no mention of what the problem was, but I'm guessing it's because I wasn't not logged in.
If you are logged in, you can comment without a problem.
There are a lot of teething issues with Penpot at the moment and I found it slower to work in than Figma. I've been keeping an eye on the project and I provide feedback to the team, and I hope it continues to improve. But right now, I wouldn't recommend it for use in production unless you're willing to make some time to log the bugs and problems you encounter along the way.