I found the secret!

When people use those inline boxes at the end of their posts for comments... the ones with the little popup to enter the secret code to prove you're a human... if I click the Finished (or Enter or whatever it is) button with the mouse instead of just tapping the enter button on my keyboard, it works!  Good grief, what a silly way to do things.  But it does work. Try it if the thing is giving you a hard time.

Also: To whoever it was that asked in a comment that I deleted by accident (sorry!), I do have bipolar disorder myself.