In case you're using Firefox on mobile - so myself and like four others - disabling Firefox' new Facebook data collection feature is quite a bit harder than on desktop, but it can be done:

  • Go to chrome://geckoview/content/config.xhtml
  • Use the search field to find the entry for aboutConfig and enable it
  • Go to about:config
  • Search for dom.private-attribution.submission.enabled and set it to false
  • Done. This only works on Android, because Firefox on iOS is just a Safari skin.

    @thomholwerda i use firefox on mobile because i need ublock origin >_> so thank you
    @eniko Yeah I use Firefox on Android for uBlock when I'm not at home (where we have a Pi-Hole to block all ads on our entire network), and because I use Firefox on desktop, and use the tab sharing feature a lot.
    @thomholwerda @eniko I have my phone rooted and I use AdAway to block all ads.
    The rest of my family uses AdGuard DNSs, have tried any of these?