Hi I have a large number of tabs that gets re-opened every time I open Firefox, but each tab is not loaded until the moment I click on it. So far, it has always been possible to see which tabs are loaded and which are not, but in the last few days it looks as if they are all loaded. That is very inconvenient! Is it an error in the new version of Firefox (I use v.55.0.2 64-bit)? Normally you can scroll through the tabs using the mouse wheel, but that does not work either. I should mention that I have Tab Groups, Tab Mix Plus, Session Manager, NoScript and AdBlock Plus. I have used them for several years. I have tried to delete the entire cache and all cookies and restart windows and delete the places database AND uninstall and reinstall Firefox. Nothing helped. All help is very much appreciated - thank you! I've tried to attach a screen shot to this message. But every time I try, Firefox crashes and must be restarted, so it simply does not work. (The same problem occurred at http://forum.mozilladanmark.dk/viewtopic.php?f=1&t=12475 ). But you can probably imagine a lot of tabs, which should have 2 different colours, but all of them look the same, except for the current tab. Best regards, Henrik R.