In-page comment reply never enables the submit button #1710
Description
This has previously worked, but in testing today, I found that I could not submit a reply in a comment thread from the in-page view. The counter changes from red when I reach the minimum length, but the "add reply" button never lights up. I can create a new comment thread and reply on the thread page; it's only reply + in-page that is broken.
I tested at 29b0054 and it worked there. This is the commit before the merge of #1702. I then tested the commit for that merge and it did not work. There is form-validation javascript in that PR that I don't understand well enough to dig further.
After we either fix or revert, we should probably publish a minor version (or amend 0.12 if that's possible).