This extension is awesome, except for the fact that EVERY time you click on a link, open a new tab or type in a website url an error pops up asking "Open this site in your assigned Container?". You are then required to click ok if you want your page to load. The Firefox forum shows several people asking for a solution, with Firefox devs stating there is no solution because "Interrupting the user every time they open a new tab is how the containers plugin is supposed to work." As far as I can see, no one has been able to find a work around yet to make it so that when you right click and "open in new tab", Firefox is actually able to figure out how to open your link in a new tab without popping up that extra prompt.