Rikj000

You can install ClassyShark3xodus,
which can de-compile apps and scan them for trackers on the fly to figure it out yourself.

Do let us know the results :)

I’d find it odd if a RPi4 can’t smoothly run a browser :o

You can use btop, to monitor if you have a bottleneck on your CPU or RAM, if Swap memory gets used, things will slow down, if your CPU is clocking @ 100%, same thing but not much you can do about that besides perhaps weeding out unnessecary processes that consume a lot, if there are any.

In case your RAM is @ 100%, you could:

• Use LibreWolf instead of FireFox,
  it’s an open source privacy focussed fork,
  which removes some of the FireFox bloaty stuff, which reduces RAM usage.
• Use uBlock Origin, to block advertisements, which will reduce RAM usage and increase page load speeds
• Use NoScript, to block JavaScript trackers, to further reduce RAM usage and increase page load speedd, beware, will block all JS by default, so sites will break, but can be manually fixed by re-enabling only the nessecary JS components on a site
• Switch to DietPi, a very light weight RAM/CPU friendly distro for SBCs like RPis, I’ve used it only headless (without GUI) but it only used 50Mb of RAM out of the box last time I monitorred it, which is impressively low.