In the past, the text of posts (including quick reply at the bottom of the thread as well as multiquote, advanced, etc.) would be saved automatically at intervals as one is typing. Recently this has been rarely working and might have disappeared totally.

It's especially annoying when you get the "token has expired" message (which seems to happen sooner than before--I had one just now at about three hours) and after you reload the page as instructed, the post you were composing is gone with no warning. You don't know before clicking to post the response that there will be a "token has expired" problem. AFAIK there's no way to initiate AutoSave before reloading the page or in fact, whenever you want a long or complicated post to be saved as you type it.

Is there a way too prevent the post that one is typing from disappearing?

I hate when this occurs. Sigh.

all I can suggest is to copy and paste it into a Notes / Doc type app or program, even an email message draft, before pressing Send or even while typing up the response. Just in case.

This can happen if you leave the page and come back to it sometime later. I experience this now and then, but only when I forget I have a tab open and come back to it.

I understand that, but in the past, I could restore the draft of my post because it was AutoSaved. In fact, sometimes if I write something and then delete if before posting, when I return to the thread even a day or so later, the draft reappears. Recently I haven't been seeing the box to click to restore what was AutoSaved.

Are you running any browser plug-ins?

Not that I know of, and I haven't changed any settings on either my laptop or my FT account.