User Agent: Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:46.0) Gecko/20100101 Firefox/46.0 Build ID: 20160425114621 Steps to reproduce: Just uninstall Firefox and install it again. Actual results: After logging in to Firefox Sync, the menu and toolbar will not be customized anymore. Expected results: The position of those icons should be included in Firefox Sync. After all, everyone uses them differently. Some use Firefox Hello, some only put in in the menu and some don't use it at all. It's a nuisance to realign them every time I uninstall Firefox or use a new machine.

Thanks for the report - we hope to get to that soon in bug 943182