If I was to play Dark Souls 3 and/or Elden ring on Linux without tearfree. There is significant screen tearing and the game feels very choppy when playing.
To enable TearFree on Xorg. You typically make a new configuration file that sits in /etc/X11/xorg.conf.d/ and append to the X configuration
https://wiki.archlinux.org/title/AMDGPU#Tear_free_rendering
There are downside to this, but I would only imagine they are problems on older GPUs.
https://unix.stackexchange.com/questions/518362/whats-the-do...
I've never noticed these downsides personally and everything seems to work great.
I don't like Wayland. It still seems very buggy and I am running Debian Trixie and would prefer to keep using X11.
But IME Wayland does have higher performance on older hardware it seems than X. My old laptop could barely play Youtube with X11 (it is the video itself not YouTube being a resource hog, I checked), Wayland performance is much better.
Did you check by downloading the video and playing it with a good standalone video player like mplayer, vlc, or mpv? If you didn't, then you didn't disentangle the web browser from the video playback.
The only thing that was different was Wayland vs X11. Same browser, same browser settings, same OS and same plugins.
Neat. Did you test outside of the browser? Based on your report, it sounds like you didn't. As you must know, the renderers in web browsers are very, very complex. I suggest you test with a standalone video player before you go blaming the underlying windowing system for performance issues.
My instance of Firefox has been configured to use only software rendering. This YouTube video <https://www.youtube.com/watch?v=tO01J-M3g0U> runs fine in both Firefox and mpv. This YouTube video <https://www.youtube.com/watch?v=WjoplqS1u18> drops many frames when played at 8K in Firefox (making it choppy and sluggish), but zero when played at 8K in mpv.
There are a great many variables in play when playing something through a web browser. That's why I suggested you re-run the test without the web browser.
Speaking of "a great many variables"...
> The machine went to sluggish and painful to use, to being reasonably decent.
Then something seems to be wrong with your Xorg config. Whether it's the drivers, the configuration of the system, or both, I don't have enough information to know. Are you running Xorg on an ARM Apple machine? That's apparently known to work very, very poorly because Apple's graphics hardware is "special". Are you running an un-accelerated Xorg video driver (like the VESA or fbdev drivers) or are perhaps using the nouveau driver on Nvidia hardware? The former would certainly be very slow. The latter is known to work fine for some folks and work really, really poorly for others.
> I don't appreciate your snark.
It's not snark. It's an earnest request to reduce the number of moving parts to make troubleshooting easier. And (as we've discovered from further testimony) the web browser wasn't even involved in the slowness... the problem is a misconfiguration of your Xorg install. We would have discovered this if you'd run the requested test, but incidental self-report works just as well.