There is a session inactivity limit of 30 minutes before you're logged off. This is for the community's security as well as your own account's security. That means that if you do nothing on the forums for 30 minutes, you may be logged off (but this also depends on your web browser's cookies and such).

If you want to write a long post and are afraid that it's going to take longer than 30 minutes to do so, I will suggest what I suggested in the old forums when people complained of lost posts... Write such lengthy posts in a word processing program on your computer and save the document. Then when you're happy with the way it looks and reads, simply copy and paste it into the forums in a new post or reply and voila! No missing posts.

Sorry this is not ideal, but even on the old forums we constantly got complaints about how the system simply ate their reply or there was a server problem and when they pressed their back button, the post was gone.

DocJohn