I switched to Firefox from Chrome a few months ago. Since then, I am troubled with the whole Firefox freezing on certain websites, ex: most airlines. If I open up a single tab, then I obviously need to wait for the whole page to load, which takes around 3s. If I open multiple tabs, pages seem to take as long as 10-15s to load and all tabs totally freeze. The same webpage combinations load perfectly fine on Chrome tabs. I am running Firefox 48.0 on Linux Mint 18 and suspect that it is related to a resource-heavy script that such websites have (maybe Java?). It is as if something in the websites get mutexes etc. and block the whole program rather than everything running on parallel threads. I tried disabling all extensions to no avail. Any help would be greatly appreciated.