Bug 33469 - video conferencing screen share not working (Cauldron/Wayland/Plasma)
Summary: video conferencing screen share not working (Cauldron/Wayland/Plasma)
Status: NEW
Alias: None
Product: Mageia
Classification: Unclassified
Component: RPM Packages (show other bugs)
Version: Cauldron
Hardware: All Linux
Priority: Normal normal
Target Milestone: ---
Assignee: Mageia Bug Squad
QA Contact:
URL:
Whiteboard:
Keywords:
Depends on:
Blocks:
 
Reported: 2024-08-15 14:16 CEST by Pierre Fortin
Modified: 2024-11-19 13:57 CET (History)
1 user (show)

See Also:
Source RPM:
CVE:
Status comment:


Attachments

Description Pierre Fortin 2024-08-15 14:16:40 CEST
Description of problem:  With Wayland, video conferencing does not work. As updates arrive in Cauldron, the symptoms change.
Initially, screen share would appear to start; but would stall with a spinner. Over time, screen/window selectors started appearing. I've tried to resolve this on my own to no avail. I wrote this on the discuss list (no response):

Hi all,

I've been hoping this was a temporary issue; but...

A few months ago (roughly), I suspect as the result of some updates, screen sharing during video conferencing stopped working.  The problem affects every possibility: Zoom app, also WebEx, Jitsi, MSTeams on browsers (Firefox, Chrome).

When I click a Share button, I get a dialog to select what to share; but when I make my selection, all I get is a spinner; other participants get a blank screen from me.

Searched for: screen sharing with kde/plasma on wayland

Found this:
https://devforum.zoom.us/t/screen-sharing-with-kde-plasma-on-wayland/71634

and this:
https://bbs.archlinux.org/viewtopic.php?id=269671

There's a test page:
https://mozilla.github.io/webrtc-landing/gum_test.html
but it's of little use for this issue; better one below.

After finding this: https://wiki.archlinux.org/title/XDG_Desktop_Portal#Backends I removed xdg-desktop-portal-gtk, rebooted and tried: https://mozilla.github.io/webrtc-landing/canvas_demo.html while I can affect the Canvas grid with the mouse, the Remote Video area remains blank. On my Windows 11 laptop, the remote area displays the grid in inverse video and tracks the changes on the Canvas.

Anyone else having this issue?  Solution?

Thanks,
Pierre

Operating System: Mageia 10
KDE Plasma Version: 6.1.2
KDE Frameworks Version: 6.3.0
Qt Version: 6.7.1
Kernel Version: 6.6.42-server-1.mga10 (64-bit)
Graphics Platform: Wayland
Processors: 20 × 12th Gen Intel® Core™ i7-12700K
Memory: 125.5 GiB of RAM
Graphics Processor: AMD Radeon RX 6600 XT
Manufacturer: Dell Inc.
Product Name: XPS 8950

Most recently: According to  https://askubuntu.com/questions/1407494/screen-share-not-working-in-ubuntu-22-04-in-all-platforms-zoom-teams-google-m this could be due to using Wayland.  I switched to Wayland because X11 had become too unstable for my liking (lots of flickering and random crashes). 


Version-Release number of selected component (if applicable):


How reproducible: always


Steps to Reproduce:
1. join a video conference with any client (app or browser) Zoom, Jitsi, MS Teams, WebEx, etc
2. Click Share screen
3. Other participants get a blank black screen.
Comment 1 Lewis Smith 2024-08-17 21:28:33 CEST
This is outside my territory; can you try airing this on the forum, which might attract the attention of another similar user?

Is "WebRTC" what we are talking about?
The Ubuntu link is interesting, but 2y old already.
Obvious question: the premise was that you need to be on XOrg for it to work, it did not work on Wayland. Did you try this?

Can you say whether it ever worked, e.g. for Mageia 9? An old or new problem?

CC: (none) => lewyssmith

Comment 2 Pierre Fortin 2024-08-18 03:04:38 CEST
Posted a query on the "discuss" list on Aug 6th.  I haven't seen a post on that list since then on any topic -- is the list dead?

You may have missed this: "I switched to Wayland because X11 had become too unstable for my liking (lots of flickering and random crashes)."

I'm too busy and lots of system activity to try X11 again. Although I just switched user, logged in with another userid on Plasma/X11 (confirmed: XDG_SESSION_TYPE=x11) and the problem persists according to the test page https://mozilla.github.io/webrtc-landing/canvas_demo.html

Yes, I was able to screen share months ago. So much has happened; it's very likely the problem started when I switched to Wayland out of frustration with X11. If X11 has had fixes for flickering/crashes, I might consider switching back; but I don't have time to "test" -- other than this issue, Wayland is quite solid for me.  That said, I did experience a moment of flickering earlier today -- hadn't seen that in a couple months.
Comment 3 Lewis Smith 2024-08-20 21:03:59 CEST
(In reply to Pierre Fortin from comment #2)
> Posted a query on the "discuss" list on Aug 6th.  I haven't seen a post on
> that list since then on any topic -- is the list dead?
Which list? In any case, I suggested the user forum, where you might find somebody who does what you do.
 
> You may have missed this: "I switched to Wayland because X11 had become too
> unstable for my liking (lots of flickering and random crashes)."
I did see this - comment 1: "the premise was that you need to be on XOrg for it to work, it did not work on Wayland. Did you try this?"
and you replied comment 2: "I just switched user, logged in with another userid on Plasma/X11 (confirmed: XDG_SESSION_TYPE=x11) and the problem persists according to the test page:
 https://mozilla.github.io/webrtc-landing/canvas_demo.html

Sad. It was worth a try. Trying that test page (actually with Falkon!) START displays a fine grid which sort of bounces, then settles down. Is this what you expect? And how does "the problem persists" manifest itself on this page?
And what has it got to do with screen sharing?

> Yes, I was able to screen share months ago ... it's very likely the problem
> started when I switched to Wayland
Your comments about X11 causing you grief, and Wayland being solid, are counter to most reports. Interesting, though. Other desktops are moving to Wayland.

Another thing is that you are a Plasma man, and one has to ask whether the screen sharing problem happens on other desktops. Understood that you cannot test this; hope the forum can offer some feedback.
Comment 4 Pierre Fortin 2024-08-25 20:57:36 CEST
It's a cool test page.  If you move the mouse fast enough, you can "shred" the "cloth".  Are you seeing a copy of the mesh below that one in inverse video?  If not, you're not "sharing". 
This works on my Ubuntu 22.04 Linux (X11) and Windows 11 laptops. I can't use those because all my work and data (over 33TB on ~70TB disk space) is on the Mageia system.
Looking at the forum, the posts are old compared to the "discuss" mailing list where I had many interactions with Dave H.  BTW, Dave said he was leaving, then came back and interacted with me and others; but that list has been quiet lately. My post on Aug 6th is the last one.
mailto:sympa@ml.mageia.org?subject=SUB%20discuss
discuss@ml.mageia.org

https://forums.mageia.org/en/viewtopic.php?f=15&t=15439 has 282 views; no replies.

Is Dave OK?
Comment 5 Lewis Smith 2024-08-27 20:26:53 CEST
You need Firefox 41, and set canvas.capturestream.enabled to true in about:config!

Well, my Firefox is 115.13.Oesr; and canvas.capturestream.enabled is 'true'.
Trying the test page again:
 https://mozilla.github.io/webrtc-landing/canvas_demo.html.
Yes, moving the mouse in the mesh does shred it - impressively.
But for:
> seeing a copy of the mesh below that one in inverse video?
> If not, you're not "sharing"
No copy as you describe, so not sharing. Do I need to configure anything else?
Comment 6 katnatek 2024-08-27 21:34:34 CEST
(In reply to Lewis Smith from comment #5)
> You need Firefox 41, and set canvas.capturestream.enabled to true in
> about:config!
> 
> Well, my Firefox is 115.13.Oesr; and canvas.capturestream.enabled is 'true'.
> Trying the test page again:
>  https://mozilla.github.io/webrtc-landing/canvas_demo.html.
> Yes, moving the mouse in the mesh does shred it - impressively.
> But for:
> > seeing a copy of the mesh below that one in inverse video?
> > If not, you're not "sharing"
> No copy as you describe, so not sharing. Do I need to configure anything
> else?

I think the information about You need Firefox 41, and set canvas.capturestream.enabled to true in about:config!

Is outdated I can see both part in lxqt (X11) and Plasma Wayland  with firefox 129.0.2 from upstream and the key not even exist neither seem necessary

This from mageia 9
Comment 7 Pierre Fortin 2024-08-27 21:54:11 CEST
My FF is 131.0a1 
Nothing else needed except, apparently, an enhanced Wayland**; I have no idea if this is in the works or where to raise an issue.

** could be pipewire: FF only has media.webrtc.camera.allow-pipewire and media.webrtc.capture.allow-pipewire -- no luck with these.
Comment 8 Lewis Smith 2024-08-29 21:08:15 CEST
It seems that we need a Cauldron/Wayland/Plasma user to try this. I will ask around, but am away for several days.

Summary: video conferencing screen share not working => video conferencing screen share not working (Cauldron/Wayland/Plasma)
CC: lewyssmith => (none)

Comment 9 Olivier FAURAX 2024-11-19 12:13:53 CET
Tested screensharing on mageia 9, gnome with zoom and jitsi.

Gnome popup asks if I want to share fullscreen or only a window, I've a little yellow screen in the notification tray.

BUT nothing is shared, blank screen.

CC: (none) => olivier

Comment 10 Pierre Fortin 2024-11-19 13:57:26 CET
Update:  I switched back to X11 a few weeks ago; it's much more stable. It rarely flickers and has shown parts of other windows in some windows; but these usually clear up by moving (focus under) mouse over these windows.

But, switching back to X11 has not helped me share.  Somehow, I also lost access to my cameras in Firefox, they work in zoom.

Note You need to log in before you can comment on or make changes to this bug.