Being able to edit posts after they have been published is a great way to deal with typos or add useful information. On the other hand this creates a situation where the original message disappears in the void due to the fact that editing will overwrite the current post. Burning Board 4.1 solves this by adding an edit history for posts which will track prior versions including the ability to restore a specific version, a notice at the post's bottom will hint for stored versions.
Moderators and administrators can view the list of stored versions and visually compare the differences between two selected versions.
Comparing versions helps one to identify the desired version and clicking on the restore button will cause the system to replace the post with the stored message.
Each version is saved in the database and adds a small piece to a growing stack of saved messages, by the time it can grow up to utilize a significant amount of storage space. We've added a pruning mechanism which will automatically purge old versions to free up some space, by default the system will remove these versions after 90 days, but the individual value is up to you.