I'm currently attempting to learn how to write Add-ons for XenForo, and in doing so I've found you need to submit a lot of forms in various ACP areas to get ACP navigation / links up and running. I was attempting to create a new Admin Navigation entry, and I was not aware that the ID field has a size limit of 25 characters, so I received an error regarding the size of this field. Seeing no other ways of getting back to the previous page I hit the Back button in Firefox 11... and the form data was erased. rageface.jpg 4 input fields and 3 dropdowns is no small order to have to re-fill out... Please fix it so that form data is preserved on pressing the browser's Back button if you're going to require this much work to create AdminCP pages. Alternatively, AJAX submit with graceful error handling like the front-end has. TL;DR: In the AdminCP, form data is wiped out when you encounter an error and go back to correct it. Needs fixing.