A few weeks ago, I started over with a fresh install, this time using Desktopify to try it out. I’d recommend it - it automatically did a couple of the necessary tweaks I had to do the first time around, along with a bunch of others I didn’t even know about.
Since you posted this, I have updated a few times, and while occasionally there were some raspi specific updates, there was nothing I noticed to be game changing. Today, I updated again, and again saw some raspi specific things. I assume there must have been something significant with the acceleration there, because the video works much better now.
I have hooked a monitor up to it to test (in addition to the 7" touch screen), and currently I am watching a 1080p movie file, outputting to the monitor in full screen at 1920x1080 resolution. Back then, my original complaint with it was that in full screen, the video became too choppy to be usable. I am happy to say this is certainly no longer the case. There is some occasional tearing on the more demanding scenes, and maybe some minor choppiness now and then, but for the most part, the video is great. And this is watching the highest resolution video I have on the highest resolution output I can do right now.
Apparently there were other changes as well. I just discovered they fixed the audio output devices. Before, you could not select HDMI or 3.5mm audio output yourself (except through command line). It picked whatever it detected on startup, and there was no way to switch between them using the sound settings (and the RPi doesn’t seem to detect when headphones are plugged in and switch automatically). But now you can select the output device from both the sound settings and the Raven devices menu. Unfortunately, this renders the applet I made both unnecessary and broken, but its great that audio it working as intended now.
I tried this tweak out, and also I tried another suggestion to set layers.acceleration.force-enabled to true. Between the two of them, it solved the tearing, but not the mild choppiness (which honestly isn’t that bad anyways). It did seem to speed up the loading of the youtube website, though.
I am suspicious that maybe the issue is that driving two monitors while one is doing full screen video is just too much for the GPU. If I just use one monitor, even if its the higher res 1920x1080 one, the full screen video is completely smooth now, no slowdown, with youtube, Plex movies, and VLC. Or maybe the driver will get better with time.
But yeah, if I stick to one monitor, even with 1080p files, the video output is fantastic.
Does sound fair that the GPU is struggling with 2 monitors etc … pretty impressive that the raspi foundation managed to produce a good GPU on such a device.
Looks like there isn’t an easy way to put a more powerful external GPU such as the bigger (several times more powerful) nvidia cards. Roll on the raspi 5 (or later!)
Providing a bundled Ubuntu Budgie as part of an customized Raspberry Pi 4 image (e.g. the Ubuntu Pi server image + modification done by @samlane) on GitHub could be great for promoting Ubuntu Budgie. There is e.g. Cubic which provides a GUI frontend for chroot. Here is a short into to how the customization with Cubic works. Or one could use chroot, schroot and/or debootstrap directly. Probably it’s even possible to make the image customization steps reproducible in an automated manner with autoinstall?