Renderer process crashes on copy/paste on Wayland (Linux Flatpak)

[christapi2099]

Environment

• Mattermost Desktop: 6.1.2 (Flatpak, Flathub)
• OS: Pop!_OS / Ubuntu-based Linux
• Desktop: COSMIC (Wayland session)
• Kernel: 6.18.7
• Runtime: org.freedesktop.Platform 25.08
• Display: Wayland (XDG_SESSION_TYPE=wayland, WAYLAND_DISPLAY=wayland-1, DISPLAY=:1)

Description

When attempting to copy and paste text into Mattermost (e.g., into the message input), the renderer process crashes and the app restarts. This appears to be triggered specifically by clipboard access on Wayland.

The crash started occurring after a org.freedesktop.Platform Flatpak runtime update (25.08).

Logs

From ~/.var/app/com.mattermost.Desktop/config/Mattermost/logs/main.log:

[error] [WebContentsEventM...] Renderer process for a webcontent is no longer available: crashed

Followed by uncaughtException in the main process:

TypeError: Object has been destroyed
    at M.getBounds (.../index.js:2:1719683)
    at k.getBounds (.../index.js:2:1695620)
    at IpcMainImpl.<anonymous> (.../4.js:1:2352)
    at T.saveAll (.../index.js:2:729916)

Workaround

Setting ELECTRON_OZONE_PLATFORM_HINT=x11 via Flatpak override forces X11 clipboard via XWayland and appears to prevent the crash:

flatpak override --user --env=ELECTRON_OZONE_PLATFORM_HINT=x11 com.mattermost.Desktop

Disabling hardware acceleration also helps as a secondary mitigation.

Expected behavior

Copy/paste should work on Wayland without crashing the renderer process.

[devinbinnie]

From what I can tell, it looks like the renderer process is crashing when you try to copy/paste into it which is throwing the exception in our application. I wasn't able to reproduce that crash myself (I'm on Ubuntu 24.04, also Wayland running GNOME).

I would suggest a couple things to try:

• a different window manager
• The latest nightly build which is available here: https://community.mattermost.com/core/pl/4z44f6htgfno8ydmmgx1yhgbcw (or you can wait until the v6.2 release later this week ;))