A useful extension for unloading inactive tabs from memory. They will reload again when you click on them. I use it together with the "Open Bookmarks Slowly" extension (with the "Discard all newly opened inactive tabs after they get loaded" option ticked in Auto Tab Discard options) so that when opening a folder full of many bookmarks one by one, each opened bookmark will be unloaded from memory immediately, otherwise the RAM gets used up and the computer slows down when opening many bookmarks.