I had previously a other add on, especially on mobile was it frustrating, you had to go in the extensions to scroll down. The swiping gesture is great! A little button to click would still be nice, that's the -1 Star.
I have a bad mind, I'm sure I will forget how to use the swipe xD so a little button at the left or tight top or better like in opera mobile, it only appears when you scroll.
There seems to be a bug when I use it on a longer page, after scrolling down, dies it stick there and every attempt to scroll up gets kicked back with a scroll down.
Maybe it's because the site is still loading all while scrolling?
I tried it in a forum where people post many images.
Btw: Reply to the people who complain that it doesn't work, that the extension will NOT work on this Mozilla website.
They must test it on other pages.