doesn't actually work the way it claims to work, see http://projectftm.com/#-b3CluYULJcy0JiPUjjUCg for the 19000KB screenshot firefox took, with missing text after the first 30% or so.
With the European GDPR(?) stuff and general cookie alerts and floating ad boxes, i find that a good 20-30% of all web pages cannot be correctly "captured" as an image. Realistically, since i can literally scroll the actual webpage and see everything, there is no reason that a screenshot wouldn't capture the exact same thing, but it's 2022 and here we are.
Sorry, my pastebin (projectftm.com) is one of the few that allows both arbitrary resolution screenshots as well as pinch/ctrl-scrollwheel zoom to arbitrary sizes. My screenshot bot uploads to a regular nginx webserver, however the screenshot id it generates is a 404. I haven't figured out how to adjust the timeout interval, as i think that's on the bot's home host side, and not the firefox side. the API has a timeout for receiving data from a remote host and if firefox takes longer than that to produce a screenshot it just gives up, even though the script has created a link.