A very underrated extension in my opinion. Firefox for Android pretty quickly runs into RAM issues if you open lots of tabs. Ideally, we should have access to a setting in Firefox to only keep a certain number of tabs "alive." If you've ever gone to a website and long pressed on many links to check out later, this extension speeds up the process vastly. I haven't encountered any issues with it, it does exactly as I expect. If you ever find yourself with lots of tabs to the point that Firefox starts to crash your phone... This extension was my fix.