Kazam video screen capture generates empty or black mp4 files

[Albert]

In Ubuntu 22.04, open kazam, select "Screencast" and below, "Area", choose an area on the screen and push enter as instructed, uncheck all 3 checkboxes (no mouse, no sound from speakers or microphone), choose to wait 5 seconds, then push "Capture". All seems to work fine; when done, go to the kazam icon and choose "Finish recording", which offers to write the video to a file with mp4 format. Do so.

The folder contains an MP4 file, but of very small size (not zero, perhaps some headers), and no video at all. VLC opens the file, runs it for all its 18 seconds, but the screen is black. Perhaps that's why the file is so small: the video buffer is all zeros and compresses perfectly to nothing.

ProblemType: Bug
DistroRelease: Ubuntu 22.04
Package: kazam 1.4.5-5
ProcVersionSignature: Ubuntu 5.15.0-48.54-generic 5.15.53
Uname: Linux 5.15.0-48-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.11-0ubuntu82.1
Architecture: amd64
CasperMD5CheckResult: unknown
CurrentDesktop: ubuntu:GNOME
Date: Mon Oct 10 16:53:32 2022
InstallationDate: Installed on 2022-03-11 (213 days ago)
InstallationMedia: Ubuntu 20.04.4 LTS "Focal Fossa" - Release amd64 (20220223)
PackageArchitecture: all
RebootRequiredPkgs: Error: path contained symlinks.
SourcePackage: kazam
UpgradeStatus: Upgraded to jammy on 2022-04-28 (164 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Paride Legovini (paride)]

I can confirm the reported behavior. Audio is recorded, video is not.

[Paride Legovini (paride)]

Looks like kazam doesn't play well with Wayland. Works fine in an Xorg session.

[Albert (sapristi)]

Thanks for the tip. I confirm that Kazam works as expected when using Xorg, recording video properly. So it's with Wayland that Kazam can't record video.