I've done that before now!
The browser BACK button will let you down on many forums and other web-based edit screens but not all! (I wish that the BACK button would work with Nabble!)
I have learned to use a text editor when making complex posts and paste it into the editor when done (only inserting the images at that final stage before hitting the "Post" button.)
Volunteer Helper - but recommending that users move off the platform!
Once the admin for GregHelp now deleted.