This script doesn't seem to work for me, it turns out your selector class "_3l3x" is not universal (its nonsense name indicates that it is dynamically generated and is likely to change). If you use a more universal selector class, this script can be much more widely usable.

(Also this is a wonderful idea for a userscript btw, I don't know why I never thought of it, but I'm glad you did.)

I get the following error when I run this script and then click on the button that appears:

Uncaught TypeError: Cannot read property 'click' of undefined
    at setInterval (<anonymous>:52:50)