[Bug]: Persisted serverColor / serverTextColor break tray menu theming (white text on white background)

[RudolfAchter]

⚠️ 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

The Nextcloud Desktop Client shows white text on white background in the system tray account menu (e.g. Pause sync, Settings, Exit).
The issue persists across restarts and ignores all Qt / GTK theming overrides.

The problem is caused by persisted color values (serverColor, serverTextColor) stored in the client configuration file.

• ~/.config/Nextcloud/nextcloud.cfg

[Accounts]
0\serverColor=...
0\serverTextColor=...

see also: nextcloud.cfg.txt

When these values are present, the tray menu is rendered with explicit palette overrides instead of using the platform theme.

Removing these keys immediately fixes the issue.

Steps to reproduce

1. Use Nextcloud Desktop Client with an existing account configuration
2. Open the system tray menu → My Account
3. Observe white text on white background in tray menu entries
4. Hover over a menu entry
   → background changes and text becomes readable
5. Restart client
   → issue persists

Workaround to fix:

sed -i '/serverColor/d;/serverTextColor/d' ~/.config/Nextcloud/nextcloud.cfg

After removal, the tray menu uses correct theme colors again.

Expected behavior

• Tray menus should follow the active Qt / GTK theme
• Persisted account branding colors must not override global UI palette
• Theme changes (dark/light) should invalidate stored palette overrides
• Tray menu text should always be readable

Which files are affected by this bug

~/.config/Nextcloud/nextcloud.cfg

Operating system

Linux

Which version of the operating system you are running.

Ubuntu 22.04

Package

Official PPA

Nextcloud Server version

32.0.3 (AIO)

Nextcloud Desktop Client version

4.0.4

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

Updated to a major version (ex. 3.16.3 to 3.17.0)

Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

Are you using an external user-backend?

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

Nextcloud Server logs

Additional info