I only in the last year got FF not to crash frequently when there is no GPU. More dependence on GPU would not be welcome. (There is no GPU access from within a VM, on Qubes.)

I can't see what benefit you expect to get from the GPU. It is plenty fast with all-CPU rendering.

The Qubes X model is interesting: each VM runs its own X, and renders windows into memory shared with a central VM that copies the pixels to real video memory. Input events get forwarded to a VM's X according to which is the active window frame. The camera can be attached temporarily to a VM, and mike input similarly. So, no VM has physical access to hardware anytime other than when you want it to.

I am hoping a future Qubes will have proxying Vulkan stubs or something, for controlled access to a GPU. But it isn't missed much since FF stopped crashing.

It's in fact not plenty fast. My PC heats up considerably watching 4k youtube videos. And in fact it stutters with 4k 60fps. How is that acceptable? How is it acceptable I cannot use one of the most popular websites optimally. And that's not even talking about all the wasted energy.

Where do you find 4k youtube videos? The best I ever encounter are 1080p. Often enough the best I can find are 720p or even worse. Not that it usually matters.

I use mpv when I am serious, moving FF entirely out of the picture.

Here are a few channels that I watch ofen that always upload in 4k. This is not a niche for serious youtube channels:

https://www.youtube.com/channel/UCsn6cjffsvyOZCZxvGoJxGg

https://www.youtube.com/channel/UCHnyfMqiRRG1u-2MsSQLbXA

https://www.youtube.com/channel/UCSpFnDQr88xCZ80N-X7t0nQ

https://www.youtube.com/channel/UCXuqSBlHAE6Xw-yeJA0Tunw

Besides even at 1080p the difference in how much battery it saves is astounding. With acceleration your CPU is just idling while without it has to work quite hard.

If they have a setup that can display and content that they want to watch in 4K without their laptop burning a mark on their lap, then that's a valid use case. An use case that doesn't work with Firefox at the moment because of Firefox. "You're holding it wrong" is an incredibly inane attitude.

What's wrong with it?

It only works under GNOME officially and that only since January. And I have in fact never gotten it to work, and I'm not alone.

As of bug 1702301 [1], and Firefox 89 currently in beta, we are shipping hardware accelerated WebRender by default on Intel (Mesa 17+), AMD (Mesa 17+) and NVIDIA (Mesa 18.2+, Binary driver 460.32.03+) GPUs, as well as lifting the desktop restriction. KDE and XFCE are allowed by default in 88. Wayland anything for a while. There are some particular GPUs with issues which we block, and there are a few more coming due to reported issues (mostly older/weaker GPUs).

There are open bugs I know. Some of which that are getting attention, others we haven't gotten a chance to prioritize. Is there a bug filed about your particular problem?

[1] https://bugzilla.mozilla.org/show_bug.cgi?id=1702301

> Wayland anything for a while

According to this : https://wiki.mozilla.org/Platform/GFX/WebRender_Where that is not true. Or is it out of date?

That is out of date, yes. It was turned on in bug 1701977.

https://bugzilla.mozilla.org/show_bug.cgi?id=1701977

Edit: Actually this is a little incomplete. It is still turned off with XWayland in late beta and release. So unless the MOZ_ENABLE_WAYLAND=1 environment variable is set, you won't get WebRender by default. I will need to review why we didn't ship with XWayland yet -- there were a couple of bugs (e.g. bug 1635186) but I don't know the status of them offhand. Expect to see movement here within the next few releases I would say.

Thanks for answering my question even though I posted it a day after this thread started.

I'm glad to hear that. One of my computers is actually using Wayland with MOZ_ENABLE_WAYLAND=1, but I haven't actually checked if it worked yet.

Will VAAPI get enabled (on X11) by default too?

VAAPI requires DMABuf, which requires EGL. We want to ship hardware acceleration using EGL instead of GLX, but CI issues have held it up (we are otherwise pretty much there for testing on nightly).

Great work!

Works for me on sway (Wayland).

I use it under KDE.

Or are you on Wayland?