I just entered a rather lengthy bug description for the Portage Development product. I forgot to select a component, and was notified of this fact in a subsequent message. Hitting the back button of my browser, I found the bug description was gone. Imagine how delighted I was about this... :-(
seems like we should punt this as a browser issue. when you hit "back", that is the browser doing the navigation, not the server, so it's not like the server can communicate the old data back in. plus, current browsers are much better at preserving in these cases. and if really need be, you can install an extension like: https://chrome.google.com/webstore/detail/loljledaigphbcpfhfmgopdkppkifgno
