This is low-bitrate (static, not dynamic), low-fps (30, not 60) video at 1x speed?
Please try to play this one: https://www.youtube.com/watch?v=6sWcB_EwhTE
And please set 1080p@60fps with 2x playback speed (gear icon in the bottom).
P.S. You can avoid ads by installing uBlock Origin addon in Firefox.
It dropped ~400 frames at the very beginning before I could bring the stats up, but then played the entire video without dropping another frame on this machine.
Unfortunately youtube stats for nerds is not the full story. Try watching 4K VIDEO TEST TV Motion - YouTube at 1080p60, fullscreen on Qubes and then compare the smoothness to any other non-Qubes device. The dropped frames count appears acceptable in Qubes, however the stuttering is jarring, especially during the panning. For videos with less motion, Qubes does a “good enough” job. For videos where motion is important, in my experience the VM refresh rate is not high enough and everything looks choppy.
I’m not saying OP shouldn’t use Qubes. As I said earlier I enjoy using Qubes for other things. I agree with unman’s suggestion to try it, but I would add that video consumption may not be the most pleasurable depending on the content that’s being watched and how sensitive OP is to choppiness.
Thanks for the report, maybe we should make some sort of table with the results if people are interested in playing Youtube at different resolutions and bitrates.
About your CPU, it is more than 2 times faster than x230 has that we discussed above. I had similar one on desktop PC and watching youtube was fine. It will drop frames on 2x from time to time (during other work on the second display), but more or less OK.
After I upgraded to 11-Gen (like 3 times faster) I noticed significant improvement of smoothness of playback. And both players were not dropping frames, just xorg was rendering them faster (maybe finally giving me real 60fps). So, this level like i7-3840QM I would describe as a minimum required for today.
Completely agree, as I mention above in my message, frame drop is not all but it is bare minimum of calling something “working”. Another thing is smoothness, that is probably about xorg being able to actually redraw the screen at least 60 times per second for 60fps videos.
I have used multiple laptops both new(latest that I used has an i7-1280P with 6p cores and 8e cores so more than powerful enough) and old with qubes and on all laptops playing a 1080p video without losing a frame(at 30fps) is impossible.
This is at odds with other users experience.
I’ll say again - this is wildly off topic, and possibly suitable for
splitting to another thread.
Whether it’s worth doing so? I don’t know.
There will be users who value playing games over security: there will be
users who value playing smooth YouTube at full screen at x2 speed over
security. Those are priorities that they set, and that they are happy
with.
Each user has to decide what their needs are, what they want from Qubes,
and what their budget and hardware availability is.
Done.
That’s true, no arguing.
My point being that when somebody is asking “Should I use Qubes?” we should point them at a drastic video-playback performance degradation when one moves to Qubes OS from any common GNU/Linux.
It will minimize the chance of dissapointment in case they value video playback a lot.
Saying that youtube works perfectly well in Qubes OS is simply not true.
Now I see that it does not work well on both old CPUs and even newest ones as @vxc and @cristiioan said. I checked it myself:
I checked the video on my 11-Gen Intel CPU. I thought that I finally have decent 1080p@60 playback in Qubes OS (not even dreaming of 4K, of course), but that video provided strong evidence that I do not. The video is played without frame drops but panning is quite choppy.
I can notice the difference especially well if I make the video/browser window very small, than it finally will become smooth.
So, the issue is indeed in X11/Qubes itself: even without frame drops it is not possible to play youtube smoothly. We probably have to wait another 5-10 years for real smooth experience of 1080p@60 on some latest CPU in Qubes OS.
I hear what you say.
As you’d expect, I think you are over stressing the extent of any
“degradation”.
For most users who come to qubes in my experience, video playback is not
an issue.(Or perhaps it is, but they just accept it and move on.)
What’s special about this use case?
Should we highlight problems with (e.g) Video editing? Mixing? 3d
modelling? Large dataset manipulation?
There are cases with all of these where Qubes will struggle.
In my experience people who come to Qubes for what it can offer,
security through compartmentalisation, accept limitations if they come
across them.
Or alternatively they’ll just wonder if it’s something specific to the combination of their hardware and qubes.
I’ve learned to be careful with audio; if it starts to stammer because I forgot and tried to play audio in two different qubes, I’ll not be able to get it to stop short of rebooting the machine. (There seems to be no way to reset the controller.)
Hardware limitation anfd/or Qubes? I have no idea.
I just deal with it.
What is special? The huge difference that make playing videos special is that Video editing, 3d modelling and etc - are niche activities, not for everybody.
And watching video is quite the opposite - everybody does it and people expect it to work properly, at least on reasonably modern hardware.
So, everybody should know in advance that watching videos (not only youtube but any videos) will be a problem in Qubes OS, especially on a laptop (due to limited cooling).
And I am talking about lowest possible HD resolution - 1080p, because proper 4K playback is not reachable for Qubes OS at all, even on any high-end mass market CPU. It should be made clear for new users to avoid possible disappointments.
I’ve been using Qubes Os for more than 5 years and I never had any problem watching and creating YouTube videos even on my old x200 ThinkPad.
I can confirm that watching YouTube Videos on my powerful Desktop computer with the I9-12900K is not really a problem for me since I do many things that requires much more power. 
While you can have some problems, that do not necessary means it is the case for everyone.
Btw, 1080p is not the lowest resolution “possible”. The lowest HD resolution is 720p (1280 x 720 pixels)
That’s quite a presumption.
Not everyone does it, and clearly even those who do have expectations
that differ from you.
I’ve reached the end of my interest here.
I never presume to speak for the Qubes team. When I comment in the Forum or in the mailing lists I speak for myself.Can you, please, open on your old Thinkpad this video fullscreen at 1080p60 in Firefox:
I know that the display of old thinkpad is not even 1080p, but OK.
It’s an outdated meaning, at least for Youtube. Youtube stopped considering 720p as HD several years ago, and remove HD label for these resolution. You can check it yourself
Time goes by, we cannot consider something like 720p still being “high” while it is actually very low compared to current state of video art with 4K+. If we do not change terms than we should still call 320p a “Standard Quality” (SD), while nowadays it is obviously not right, 320p is a low-quality garbage, and “Standard” is more close to 1080p.
Can you, please, open on your old Thinkpad this video fullscreen at 1080p60 in Firefox:
No, nobody cares about frame drops while watching a YouTube Video. I’m not a Fortnite gamer, LOL. So, like I said, I see no problem, no lag while watching YouTube videos on my ThinkPad…
It’s an outdated meaning, at least for Youtube. Youtube stopped considering 720p as HD several years ago, and remove HD label for these resolution.
That’s completely false. No one can change facts. In fact, Google/YouTube itself still considers 720p as an HD resolution.
Recommended resolution & aspect ratios
For the default 16:9 aspect ratio, encode at these resolutions:
- 4320p (8k): 7680x4320
- 2160p (4K): 3840x2160
- 1440p (2k): 2560x1440
- 1080p (HD): 1920x1080
- 720p (HD): 1280x720
- 480p (SD): 854x480
- 360p (SD): 640x360
- 240p (SD): 426x240
Source: Google itself
Time goes by, we cannot consider something like 720p still being “high” while it is actually very low compared to current state of video art with 4K+.
Why not?! In networking, FastEthernet is called “fast” even if it’s speed is 10 times slower than GigabitEthernet. Although FastEthernet is significantly slower than GigabitEthernet, with a maximum data transfer rate of 100 megabits per second (Mbps) compared to 1000 Mbps for GigabitEthernet, it is still considered “fast” in the context of networking.
What are you trying to prove here?! 
So, you suddenly realized that your old Thinkpad is not able to play YouTube videos at 1080p@60 without frame drops, not even speaking about smoothness.
And instead of posting results decided to say that no one cares about frame drops. OK, I see, smart. The next step is to say that no one cares for YouTube videos at all. Because you have right to decide for everyone what they need.
Some outdated FAQ question on google domain means nothing compared to millions of videos on YouTube itself.
Check yourself: open any YouTube video, and change quality to 720p and check yourself that HD label disappears. It will prove you that 1080p is the lowest possible HD-resolution nowadays on YouTube as I said.
So, you suddenly realized that your old Thinkpad is not able to play YouTube videos at 1080p
You’re making assumptions without evidence. 
“What can be asserted without evidence can also be dismissed without evidence.” 
I can watch 1080p YouTube Videos on my x200 ThinkPad smoothly and without any lags. That what’s the most important thing for me. I don’t use Qubes Os as a Benchmark platform…
Because you have right to decide for everyone what they need.
Says the one who literally said, " watching video is quite the opposite - everybody does it".
Well, standards can’t be changed by Youtube. The 720p is one of the defined resolution thresholds for video content. It doesn’t matter if you like it or not
Some outdated FAQ question on google domain means nothing compared to millions of videos on YouTube itself.
Stop trolling you’re not even funny, the Google page was updated 3 years after that Youtube removed the HD label for 720p on their videos.
You cut the sentence, removing the main part about without frame drops and smoothness. I have to repeat it for you:
Is it not true?
If not, can you provide the results of proposed tests on 1080p@60 video above?
We aren’t on Reddit.
It’s natural to want to feel right, but it’s important to recognize that being right isn’t always the most important thing. Instead of focusing on being right, try to focus on understanding the perspectives of others and engaging in productive discussions.
If you’re dealing with a specific issue or problem, it’s okay to raise your problem and ask for help there, but that does not mean that everyone is facing the same problem.
What you don’t understand when me and other users say that we have no performance issues when watching YouTube videos even on old hardware like my x200 ThinkPad ?
Simple question, simple answer.