Can't screenshare on Wayland (Linux)

[vixalien]

Summary

When using linux in a channel, I can't share the screen, as mac users can.

Description

Steps to reproduce:

1. Open Zed
2. Join Channel
3. Try to share screen
4. There is no share screen button

Expected Behavior: screen share button
Actual Behavior: No screen share button

[tidely]

Are you using Wayland or X11? What version of Zed are you using?

Linux only recently got screensharing support for X11 #27807
However Wayland is not yet supported.

[vixalien]

I see. I'm using Zed on Wayland. Sorry I forgot to paste the system information

Zed: v0.181.7 (Zed) 
OS: Linux Wayland org.freedesktop.platform 24.08
Memory: 31.1 GiB
Architecture: x86_64
GPU: Intel(R) Iris(R) Xe Graphics (TGL GT2) || Intel open-source Mesa driver || Mesa 25.0.3 (git-c3afa2a74f)

X11 is usually considered insecure, and for implementing screencast using Wayland (with portals), the ashpd library may be utilised: https://bilelmoussaoui.github.io/ashpd/ashpd/desktop/screencast/index.html

[vixalien]

cc @mgsloan maybe you can let us know why it only works on X11

[mgsloan]

@vixalien Sure! Since the scap library is cross platform, I'd hoped it would simply work on Wayland. However, it didn't work in my testing, and collaborators see all green for the screenshare. The wayland-screenshare branch has the changes needed to enable Wayland screenshare. It may be worthwhile for some Wayland users to try this branch, it's possible that something is misconfigured on my machine.

There will also need to be changes to get it to pass CI. In particular, this build failure. Searching for that error revealed pop-os/cosmic-epoch#280 which says that you need libspa version 1 instead of libspa version 0.3.

[IGLOU-EU]

Hi @mgsloan,
I tested your branch but it doesn't work.

I'm not a Rust guy (I try to do), so after few attempts, I asked Sonnet 4 😅.
He made this autosigned commit (Sonnet did the work, not me):
IGLOU-EU@cd6fcd7
If by any chance you can use this "POC" to create a nicer implementation, that would be awesome :p

[mgsloan]

@IGLOU-EU thanks! I gather that this implementation works on your machine?

[IGLOU-EU]

@IGLOU-EU thanks! I gather that this implementation works on your machine?

Yes that "work", but pipewire capture is done with test pattern...
Sonnet have made some doc in the PR, and propose ffmpeg or gstreamer lib usage.
I followed one of there's advice and looked the obs implementation find here obsproject/obs-studio#4287 for understanding (spoiler I don't ...)

And after some search, I found this implementation in rust (not tested) https://github.com/Adonca2203/waycap-rs

Hope that can help :S

[Adonca2203]

Hey, maintainer of waycap-rs here!

This might be something I can assist with.

My best guess (without looking too deeply at the code) is that the current screen share implementation does not go through xdg to ask the user for permission to record their screen to feed to pipewire.

I can take a closer look in a bit

[vixalien]

Thank you!