Screen sharing black screen on newest Linux deb version on Ubuntu 22.04 XOrg

1. I am running Ubuntu 22.04 on a Lenovo Laptop with NVIDIA 550 drivers under X11. Wayland doesn't work for many applications.

2. I was running Zoom 6.4.5.1259 with problems on both Wayland and X11

3. I downgraded as mentioned below to 6.1.6.1013 as documented below.

4. Zoom works as expected,

On Wayland the problem was a combination of the new versions of Zoom and Wayland interaction, not only with Zoom but with the programs Zoom is trying to interface with. When I switched to X11 the new version of Zoom still had difficulty switching shared screens.

I was prompted to investigate Wayland to see what I was faced with. It turns out that Wayland has added security features that prevent one program from accessing the screen of another program. Zoom is not the only program that doesn't play well with Wayland. As an engineer a large number of programs I use regularly either have problems with Wayland or just won't work. It seems Wayland has targeted a lot of developer and scientific programs to make them unusable. At any rate, I found that Zoom had the most trouble with those programs that also had problems with Wayland. So it isn't just Zoom, but also the program Zoom is sharing. The fact that older versions of Zoom work, means we are living on shared time before these older versions will become obsolete and we will have to upgrade to a potentially non-working version. Given the fact that if the program screen to be shared may be a problem for Wayland, I don't see how Zoom can even solve this problem and will have to carry X11 support as well as Wayland for a long time. Otherwise people who have to get work done and can't do it in Wayland will cease to be Zoom customers.

Zoom 7.1.5 on Xubuntu 26.04 / X11: local screen freezes during screen sharing; xcompmgr workaround

I am seeing what appears to be a related issue with Zoom 7.1.5.4332 on a fresh Xubuntu 26.04 installation.

Symptoms

When I start screen sharing, my own desktop display freezes on a static image. I can no longer visually follow what I am doing locally.

However, the screen share itself continues to work correctly: other meeting participants can see my screen normally and can see all mouse/window/application actions in real time.

Stopping screen sharing is not possible anymore

Environment

Zoom: 7.1.5.4332
OS: Xubuntu 26.04
Desktop: Xfce 4.20
Session: X11
X.Org: 21.1.22
GPU: VMware SVGA II Adapter
Kernel driver: vmwgfx 2.21.0.0
OpenGL: Mesa 26.0.8
Renderer: llvmpipe (LLVM 21.1.8, software rendering)

Xfce compositing was enabled:

$ echo $XDG_SESSION_TYPE
x11

$ xfconf-query -c xfwm4 -p /general/use_compositing
true

Changing Zoom's available screen capture modes (Auto, Original, PipeWire, PipeWire Remote Control) did not solve the problem.

Working workaround

Disable xfwm4's built-in compositor:

xfconf-query -c xfwm4 -p /general/use_compositing -s false

Then start xcompmgr:

xcompmgr -c -l0 -t0 -r0 -o.00 &

With xcompmgr running instead of the xfwm4 compositor, Zoom screen sharing works normally and the local desktop no longer freezes.

Zoom also prints X11 errors such as:

BadWindow (invalid Window parameter)
BadDrawable (invalid Pixmap or Window parameter)
BadRegion

This looks like an interaction between Zoom's X11 screen-sharing/rendering code and xfwm4 compositing, possibly made more visible by the VMware/llvmpipe graphics environment.

I can provide additional logs or run tests if useful.