[Bug]: nextcloud-client shows empty transparent GUI on gnome-xorg

[recolic]

⚠️ Before submitting, please verify the following: ⚠️

• This is a bug, not a question or a configuration issue.
• This issue is not already reported on Github (I've searched it).
• Nextcloud Server and Desktop Client are up to date. See Server Maintenance and Release Schedule and Desktop Releases for supported versions.
• I agree to follow Nextcloud's Code of Conduct

Bug description

Nextcloud GUI doesn't show up on gnome-xorg. (but it works perfectly on gnome-wayland).
After initial configuration, if you start nextcloud client again, the GUI doesn't appear. Windows manager shows a transparent window (Screenshot attached)

This issue could be easily reproduced in fresh-installed Arch Linux, on both laptop, desktop, and QEMU virtual machine. I tested different AppImage, showing:

NextCloud client version	Result
3.15.0 from Distro-Repo	Bad
3.15.2 AppImage	Bad
3.12.8 AppImage	Bad
3.12.1 AppImage	Bad
3.11.2 AppImage	Bad

Note1: Nextcloud client doesn't print any abnormal error message. Sometimes, I just keeps trying, it sometimes (rarely) randomly fixed itself. I don't know the reason.

Note2: I always kill the background nextcloud daemon before doing my test. Doesn't make any difference.

Steps to reproduce

1. Deploy fresh minimal Arch Linux installation.
2. Install the following packages.

pacman -Sy --noconfirm fish dhcpcd vim sudo openssh
useradd --create-home --shell /usr/bin/fish recolic
echo 'recolic ALL=(ALL) NOPASSWD: ALL' | sudo EDITOR='tee -a' visudo

pacman -Sy --noconfirm gnome networkmanager power-profiles-daemon nextcloud-client firefox xorg-server
systemctl enable gdm NetworkManager power-profiles-daemon

3. Reboot. When login, choose gnome (wayland). In gnome, start nextcloud client. This is good case, everything works in wayland.
4. Reboot. When login, choose gnome on xorg. In gnome, start nextcloud client. This is bad case, GUI doesn't show up. You got a repro.

Additionally, you can try downloading different version of AppImage. It repros on 3.15.2, 3.12.8, 3.12.1, 3.11.2, and all older version.

Expected behavior

Nextcloud client GUI should show up.

Which files are affected by this bug

/usr/bin/nextcloud

Operating system

Linux

Which version of the operating system you are running.

Arch Linux rolling

Package

Official Linux AppImage

Nextcloud Server version

N/A (this issue is not related to server side)

Nextcloud Desktop Client version

Tested 3.11.2, 3.12.1, 3.12.8, 3.15.0, 3.15.2

Is this bug present after an update or on a fresh install?

Fresh desktop client install

Are you using the Nextcloud Server Encryption module?

N/A (this issue is not related to server side)

Are you using an external user-backend?

N/A (this issue is not related to server side)

Nextcloud Server logs

N/A (this issue is not related to server side)

Additional info

I tried to set environment variables such as

QMLSCENE_DEVICE=softwarecontext
QT_OPENGL=software
LIBGL_ALWAYS_SOFTWARE=1

no effect. Other QT application (such as qBitTorrent) works fine on the same machine.

This bug doesn't affect nextcloud-client functionality. It still sync files in background if I did configuration in wayland session.

[recolic]

I will do more experiments in other distro, other Desktop Environment, and see if it repro elsewhere.

[recolic]

note for QT related error message:

Update: these messages are not related to this issue. I compared wayland impl & x11 impl by running

bin/nextclouddev --logdebug --logfile /tmp/way.log # GOOD
env QT_QPA_PLATFORM=xcb bin/nextclouddev --logdebug --logfile /tmp/x.log # BAD

and compared them. Both of them have these errors.

note: This problem never repro on wayland, not even once.

[PhMetzger]

I'm experiencing a similar issue with the PPA version on Ubuntu 24.04, affecting both Xorg and Wayland. The main application window fails to appear, although the parameters window works as expected.
There are no error messages or output in the console when launching from the command line.

This issue did not occur with the previous PPA version (3.14).

[PhMetzger]

Solved in last PPA version (3.15.2)

Thank you :)

[recolic]

Hi @PhMetzger your issue is different.

To make it clear: this issue (#7685) is not solved.

[wirepatch]

Joining he club! I'm on current Fedora Core 41. The screenshot shows the non-fedora flatpack version offering two sub windows. One of them is actually empty / transparent.

The Fedora distribution's version is even worse: Nothing shows up at all sometimes and there is now choice as in the above screenshot. You have to quit using right mouse click and restart the beast. This sometimes has to be repeated several times until eventually the window becomes visible. Totally unusable