This app is totally useless and a waste of space. When you go to look for your tabs, half of the time they're missing anyway. Why doesn't Firefox change the settings instead and not allow sites like Ebay to open 50 million windows every time you look at a listing. The multiple windows never use to be a problem, so maybe Firefox needs to address this issue so we don't have to have useless apps like 'One Tab' taking up space on our computers just so Ebay can open another, and another, and another window that will be wasting up space in the 'One Tab' app.