Latest update to LibreWolf changed it's user agent string and it's causing websites to freak out. For example amazon will default you to a mobile website and Youtube music is having issues. To make matters worse if you try to download an extension to change the user agent string, it won't let you and tell you to download Firefox. You'll need to manually override the user agent string by going into about:config. You'll need to add general.useragent.override string into config.