I'm running Firefox 122.0.1 on a Windows 10 desktop PC, with a profile which includes a userChrome.css file which makes several layout and cosmetic changes. I also have a laptop (also Windows 10) which has an old Firefox 97.0.1 installation, and I'd like to make the same changes on this machine which I'm used to on the main computer. I copied my desktop profile to the laptop, to the same directory as its present profile, but when I rebooted Firefox the transferred profile wasn't recognised. While doing the transfer I received error messages about some of the folders: ''Destination path too long''. This despite the fact that the registry flag to accept extended paths is set to '''1'''. I had to skip several folders in order to complete the transfer. Could this be the reason why the new profile isn't being picked up? Or is it because the two Firefoxes are of different versions? I'd be grateful for any thoughts. Many thanks.