@gemlog It's not always perfect, especially on "infinite scrolling" websites, but in most cases I use it for it gets the job done. It also snaps to the edges of the element you are about to capture the same way AdBlock picker does — it highlights the element when you hover over it, comes in handy sometimes. In case you want to try it out, it's Ctrl+Shift+S, but maybe you have to enable something in about:config to enable advanced features — I don't remember, if that's the case, I did it long ago