It would be more handy if it appears straight in the website, a scrollbars like in opera would be great. I really miss that! I wish opera and Firefox mobile would work together to make a good mobile browser.

Unlike the given screenshot it's 3 step method. 1st click on the 3 dots, then "Add-ons", then "Scroll to bottom". It's always under the Ad-ons not under 3 dots. Thought no problem with its functionality.

Doesn't work on Firefox new tab page and maybe others, but works on websites. However, the menu option to scroll dissappear after closing the app. Going to addons page and disabling then re-enabling puts menu entry again