Invalid Form Validation errors

A number of users are finding that when they try to post a comment/reply or send a Private Note, they are getting the error "Invalid Form Validation received - please refresh and try again". There seems to be no reason for this error.

I have seen this myself when sending a Private Note (Windows PC with Firefox). I copied the text, refreshed the screen, pasted the same text and the note sent without error. Subsequent notes to the same person went OK.

I have just tried to respond to a support ticket about the same issue and I got the Invalid Form validation error. See screenshot - you can see there is nothing untoward in the text.
I copied the text, refreshed, pasted and made a couple of changes. When I clicked "update ticket" I got the same error. On the third attempt the ticket was updated correctly.

Any ideas as to the cause?
updated by @lornawebber: 04/07/18 03:32:28AM

I've been trying to update a comment containing an image and I have tried multiple times, refreshing the page, cancelling out and repeating etc., but I am still not able to update the comment. I keep getting the Invalid Form error whenever I click Update.
https://pmp-art.com/comment/update/id=1154981
on this discussion https://pmp-art.com/library/group_discuss/571/30-30s-in-2017

Screen shots attached (the first one seems to have missed off the bottom part of the image).
I attach a screenshot of the code in the comment I'm trying to update.
updated by @lornawebber: 01/02/18 08:02:00AM

I was able to update that comment first time after waiting about an hour.

So in Jamroom every form has what's called a "form session" - this is basically information about the form that the core uses to do things like validation, CSRF protection, etc. When you get this error it means that Jamroom was not able to find the form session that was being requested. This really shouldn't happen and would indicate something messed up in the user session. Logging out and back in again should fix it up, but again - you should rarely see this.

If you find you are consistently getting this error than it likely indicates there's something else going on and we need to check it out, so open a support ticket and we can investigate.

Thanks!


--
Brian Johnson
Founder and Lead Developer - Jamroom
https://www.jamroom.net

We are getting this a lot. I raised a ticket. Thanks.