That is a good tip and one I usually use when commenting on some forums online that are known to be a bit "flaky". And so I have already started doing it here. The thing is, as my day job is as a web developer, I know that AirBnb has some cutting edge technology on the front-end, and this could easily be prevented from happening. Not the bug itself - and it is a bug and not intended behaviour (or why would I get a bug id to report?) - as that happens in all software, but the losing of data.
If AirBnb had taken the time to ensure the content was saved in the browser before posting it to the server, it would be possible to restore the content if pressing the Back button in the browser. That is why I am a bit unamused. All these tech resources, yet spending one hour of development to implement this basic feature has not been done.