Weird Error "Cannot Edit Comment"

[TwoCalories]

This has never happened to me before, and the comment has only been out for less than a day. I've edited posts that are months old (don't ask me why, I just do). Is this new? Or is this induced by all the errors that have been going on with the forums these days?

UPDATE: I've tested a newer comment and an older comment than the one above, and I was able to edit both successfully.

A post from a forum game, where I added the "test" in asterisks.

A several month old post from my mission report, where I added "test" in asterisks again.

[TwoCalories]

UPDATE x2: I was able to edit the original post where I got the error. I included a new picture in the edit, and not including the picture fixed it. I still have no idea why this happened though, and it was pretty annoying to have to remake the edits, so help will be appreciated.

[Vanamonde]

Yay, more weirdnesses! Sorry for the trouble. We've alerted the guys. 

[Hotel26]

I am finding that if I wait a long time and then attempt to edit/include some plain text, I can Save the change successfully.  The post then goes back to being locked for a long time.

Q. What is a "long time"?
A.  Don't know, but will test & report...