[Bug]: No shadows on Linux KDE (Wayland)

[heroin-moose]

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• I have checked the issue tracker and have not found an issue that matches the one I'm filing. This should include closed issues.
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• This issue reproduces on the most recent stable version, or the most recent prerelease version of the Mattermost Desktop App.
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Mattermost Desktop Version

5.11.2

Operating System

Arch Linux x64

Mattermost Server Version

No response

Steps to reproduce

1. Boot into KDE 6
2. Start the app

Expected behavior

1. The main window should have shadows

Observed behavior

1. The shadows are gone

Log Output

-

Additional Information

Not technically a bug, more of a regression from 5.8.x. This seems to be related to #3104, i.e. the electron version bump. While not a bug per se, it's kinda annoying because the window blends in and it's harder to distinguish there are more than a couple of open apps on a desktop. Dunno much about Electron, but if it's possible to restore the old behavior (asking a compositor to draw SSD instead of manually drawing CSD), it would be probably the best way to go.

[devinbinnie]

I don't think there's anything we can do about this other than upgrade Electron, have you checked the Electron GitHub to see if this is reported? Also a screenshot would help.

[heroin-moose]

have you checked the Electron GitHub to see if this is reported

Nah, I'll try, but I think that's an API change, not a bug. I suspect that electron now requests CSD instead of SSD by default. I'll check what Wayland debug logs say.

Also a screenshot would help.

Sure.

Mattermost 5.8:

Mattermost 5.11:

This is KDE 6.3 (Wayland).

[devinbinnie]

I was able to see this myself on KDE, just to double check do you have the ELECTRON_OZONE_PLATFORM_HINT=wayland environment variable enabled?

[heroin-moose]

No, I don't, newer Electron choose wayland by default AFAIR.

[heroin-moose]

Checked with ELECTRON_OZONE_PLATFORM_HINT=wayland, same.

[devinbinnie]

Created a JIRA ticket to track: https://mattermost.atlassian.net/browse/MM-63584