Would be perfect if it could ACTUALLY capture the WHOLE really loooonng webpage like extensions in Chrome do. I'm not sure if it is a Firefox Quantum's shortcoming or something but it just can't capture to the end of webpages of extreme length, the lower part of the page is just white and blank. Please look into this problem. Thank you!
P/s: You can test on one long scrolling webpage like this one: http://psychologytoday.com/ and you will get what I mean.