[Bug]: Background pictures which invert the heading icons do not invert the logo

[jancborchardt]

⚠️ This issue respects the following points: ⚠️

• This is a bug, not a question or a configuration/webserver/proxy issue.
• This issue is not already reported on Github (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• Nextcloud Server is running on 64bit capable CPU, PHP and OS.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

When picking a light background, the navigation icons invert but the logo stays white, looking inconsistent.

Steps to reproduce

1. Go to "Appearance & accessibility"
2. Pick a light background
3. See how the app icons invert, but the logo not

Expected behavior

If the logo is still our default Nextcloud one, we could also invert it as it looks much nicer. Themed logos should of course not be inverted.

Installation method

No response

Operating system

No response

PHP engine version

No response

Web server

No response

Database engine version

No response

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

No response

Are you using the Nextcloud Server Encryption module?

No response

What user-backends are you using?

• Default user-backend (database)
• LDAP/ Active Directory
• SSO - SAML
• Other

Configuration report

No response

List of activated Apps

.

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

No response

[jancborchardt]

cc @Pytal @juliushaertl

[szaimen]

See #34615