I loved this extension until the update 2-10-19. It has completely stopped wporking for me. I'mk using the latest version of Firefox for my system, version 65.0.1, (64 bit). I made sure that Firefox was saving all history, checked for any possible updates for it. Nothing happens, even with multiple clicks. It was good while it lasted. Really bummed that I have to go find another app since this one has not worked for 3 days and I use the web for hours daily, and no matter how careful I am, I always end up closing the wrong tab now and then.