Click the toggle button to turn it on!
Highlight something (hold down mouse button, drag over it)
Release the mouse button......
BAM IT's A QR CODE
Sounds easy, super simple... BUT THE APPLICATIONS ARE ENDLESS!!!!
toggle the addon off, and you can go back to highlighting things to copy and paste ;)...
Changes aren't permanent, refresh the page and anything you turned into a qr code will return to normal ;)