Events:

  screenshots.canceled#canceled
  screenshots.copy#copy
  screenshots.download#download
  screenshots.failed#failed
  screenshots.selected#selected
  screenshots.started#started

Counters:

  screenshots.copy
  screenshots.custom
  screenshots.download
  screenshots.element
  screenshots.full_page
  screenshots.upload
  screenshots.visible

inb4 mention of “Send technical and interaction data to Mozilla” setting, like it's okay for software to be privacy-adversarial by default lol