Comment 27 for bug 2020782

Although Mustafa says he's not well-versed, he's way smarter than me :) So his comment#26 seems to be much more relevant than what I have to say, but I'd like to reply to Daniel's comment#24/25 anyway:

I saw the details you mentioned on comment #16, and I also have fractional scaling turned off. By "having it off" I'm assuming this [1] is enough, right?

Also, I noticed that by previous pasteboard wasn't too clear in showing the problem when I use 42.5-0ubuntu1vv5. I want to clarify that I get a screen as if I had 3 monitors side by side, but all in the same "client monitor". If you try to maximize the application, it picks one of the "screens" and maximizes to it, as we can see here [2].

Even without changing the fractional scale or scale setting, just by having the 42.5-0ubuntu1vv5 packages installed, I get this "triple monitor in 1" situation when I boot my VM. I had to reinstall the original packages from our archives in order to fix this. Also, I just want to make sure you're aware that these are the *mutter* packages that I have installed:

ubuntu@jammy-dcv:~$ sudo dpkg -l | grep mutter
ii gir1.2-mutter-10:amd64 42.5-0ubuntu1 amd64 GObject introspection data for Mutter
ii libmutter-10-0:amd64 42.5-0ubuntu1 amd64 window manager library from the Mutter window manager
ii mutter-common 42.5-0ubuntu1 all shared files for the Mutter window manager

i.e. Just want to make clear that I don't have the "mutter" package installed, but the ones above.

Back to your comment, iiuc, the "Impossible to set scaling on crtc 65 to 1.000000, error id 2" means that we're trying to use some incomplete RandR implementation in Xdcv. Isn't it the fractional scaling, that was effectively removed from your 42.5-0ubuntu1vv5 package? In this case, doesn't the errors showing up means that we're still trying to use something that isn't properly implemented in Xdcv?

Just for my own information, what's the difference between the vv5 and vv4 builds?

Tested with vv4 in a VM:

ubuntu@jammy-dcv:~$ sudo dpkg -l | grep mutter
ii gir1.2-mutter-10:amd64 42.5-0ubuntu1vv4 amd64 GObject introspection data for Mutter
ii libmutter-10-0:amd64 42.5-0ubuntu1vv4 amd64 window manager library from the Mutter window manager
ii mutter-common 42.5-0ubuntu1vv4 all shared files for the Mutter window manager

As soon as I installed it in my VM, I got that "triple monitor" situation again, and then I realized it's really just what you had described, that it automatically enables these other monitors. I can disable them and get back to 1 single monitor. With vv4, I can apply the scale 200% [3] and then revert it, but then it changes my resolution to 800x600.

After realizing that, I went back to the vv5 package and re-tested and I notice it's the same behavior as in vv4. After installing it automatically enables all 4 monitors, I have to manually disable them and keep just 1. Then I test the scale to 200% + revert and it does revert, but also changes my resolution to 800x600.

I can't really test that in Workspaces, because when it enables the extra monitors, I'm no longer able to access the Workspace with the AWS Workspaces client. If I try to change the scale in Workspaces, I believe it tries to enable the other monitors, and then all I get is a blank screen.

And here's the output of "xrandr --verbose" from the VM [5] and the Workspace [6]

[1] https://pasteboard.co/qEbvvwijUW2F.png
[2] https://pasteboard.co/K9Oh9nZ8wqNk.png
[3] https://pastebin.ubuntu.com/p/xkcFScZv5c/
[4] https://pastebin.ubuntu.com/p/mVwWt4Rzsr/
[5] https://pastebin.ubuntu.com/p/JC4PXwdv55/
[6] https://pastebin.ubuntu.com/p/S5bXz975Nn/