Memory Leak recently (20GB Ram usage even when closing everything), sporadic high CPU usage for no reason, sometimes 30% on an modern 8-core CPU, again even when closing all tabs besides an empty tab (the extension wasnt used or opened at all in either of those situations). Firefox performance analyzer clearly showed it was coming from this extension.
Besides that, the user interface is clunky and doesnt work correctly if the extension icon is moved into the dropdown menu.