horrifying-pdf-experiments VS profiler

I think this is it: https://github.com/osnr/horrifying-pdf-experiments

Here's the link to horrifying-pdf, a GitHub repo with a link that lets you play breakout entirely inside a PDF file.

Apparently PDF's have enough weird functionality that you can even build a simple video game in them. Check out https://github.com/osnr/horrifying-pdf-experiments

You can even play games embedded into your PDF file

If you're mocking me for avoiding client-side scripting then without discipline PDF is hardly any better. I disable JS by default (and only turn them for e.g. to reply to you here because Reddit decides to inject forms instead of hiding them via CSS) and the browsing experience is a lot snappier.

[1]: https://github.com/osnr/horrifying-pdf-experiments

Depends on your PDF viewer... https://github.com/osnr/horrifying-pdf-experiments

Probably your best bet is to use the Firefox Profiler once it starts hogging the CPU to try to see what it's doing. I'd be happy to take a look at the result although I don't have a lot of experience at diagnosing performance problems; hopefully the profile will make it obvious what's going on.

I tried using the https://profiler.firefox.com/ and running with:

You can try to reproduce while taking a profile using the Firefox profiler, then share it in the #perf:mozilla.org room on Mozilla's Matrix instance.

Run a profiling session for ~30 sec when you notice something is running slower than you expect, see https://profiler.firefox.com/. Share results here if you want help interpreting them.

Next time, send a SIGABRT to the main process (kill -6 $(pidof firefox)) and use the resulting backtrace (you will find a link to the crash report in about:crashes) to file a bug. A performance profile could be useful, but you'll need to know first what to capture. This seems like a graphics issue, so try the Graphics preset. Share a link to your report.

https://profiler.firefox.com will be useful if you can capture and share it to developers.

If you can reproduce it in safe mode and a clean profile, capture a performance profile using the clean profile while trying to load a problematic webpage, don't remove any information from it, and share it here (although it's typically not easy for users to analyse them), or file a bug with it attached.

Next time, capture a performance profile using the Graphics preset, and kill the browser by entering kill -6 $(pidof firefox) in a shell. This will create a bug report (unless debian disables the crash reporter) that would indicate where Firefox is stuck at. You might need to use an official build to get useful results.