(community flatpak) KDE + dark mode: darker window background colors result in brighter panel background (and therefore bad text visibility)

[tamius-han]

⚠️ 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 have searched for 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

In KDE, setting window background color to a darker color will increase brightness of the panels in the Nextcloud window. This results Nextcloud displaying white text on almost white backgrounds.

This issue is present in the community flatpak, as well as in the package . However, it does not appear to be present in official AppImage.

Steps to reproduce

1. Open nextcloud settings window
2. Open KDE system settings and navigate to Color and themes > Colors
3. Choose Breeze Dark, and click 'edit'
4. At this point, Nextcloud window should appear like so:

5. Click 'window background' and set it to black Save the color scheme, close the edit dialog, and click apply in the main settings window.

6. Observe Nextcloud not respecting your wishes. Despite window background being set to darker color than before, panels in the Nextcloud window gain background color that's brighter than it was before

Expected behavior

Changing darker window background color should not brighten the panels. Instead, panels should be darker than they were before:

Which files are affected by this bug

n/a

Operating system

Linux

Which version of the operating system you are running.

Linux 7.2.6-1-cachyos #1 SMP PREEMPT_DYNAMIC Thu, 17 Sep 2026 10:26:35 +0000 x86_64 GNU/Linux

Installation method

Community FlatPak (please test with the AppImage package ?)

Nextcloud Server version

n/a

Nextcloud Desktop Client version

Flatpak / 34.0.4daily

Did this occur after an update or on a clean installation?

Clean desktop client installation

Are you using the Nextcloud Server Encryption module?

No

Are you using an external user-backend?

• Default internal user-backend
• LDAP or Active Directory
• SSO - SAML
• Other

Nextcloud Server logs

Additional info

According to my testing, this bug seems to trigger if background color is set to #181818 or darker. If window background color is set to #191919, dark mode seems to work correctly.

This issue has been present for quite some time, I only now got annoyed into reporting it.

While I have found similar open issues that involved dark mode, they seem to revolve around incorrect text color or nextcloud being stuck in light mode, but none of them seem to revolve around the panel background color. There are several apparent duplicates in closed issues, but those appear to be closed as completed in an earlier version.