Each time I need to edit a message on this community, I can't. I always get the message :
Your post has been changed because invalid HTML was found in the message body. The invalid HTML has been removed. Please review the message and submit the message when you are satisfied.
The problem just happened while posting this question for the very first time.
refresh the page and you will be good to go.
you can also try deleting cookies in your browser preferences but with a refrsh the page you should be able to repost
that normally happens when you've been browsing ither threads for too long amd then come back to your opened webpage, which seems to have a timeout or an expiration period if the page is abandoned for too long.
If this also happening even if you refresh the page?
Try using a different browser. Limit the amount of time you spend in the Reply field. If another person replies to the same post at the same time you're writing a reply, you could get locked out. It sometimes happens to me. I just copy my text and refresh the page.
Thanks @Nancy_OShea & @ls_rbls.
Let's try your ideas while writing this anwser.
Edit1: I've got the problem whil writing the answer. I can clicked on "Post" a second time, and my answer has been correctly published.
Edit2: Refreshed the page seems to help. Thanks.