[Bug]: Warning for X-Robots-Tag raises for the none value

[jooola]

⚠️ 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

After upgrading to 25.0.5, I've checked the admin dashboard, and the I had the following warning:

"The X-Robots-Tag header is not equal to noindex, nofollow."

But I configured my web server to set this header to none which translates to noindex, nofollow.

From my nginx configuration:

  add_header X-Robots-Tag "none" always;

So I think the check should also include the none value.

Steps to reproduce

1. Configure the web server to set the X-Robots-Tag header to none
2. See warning

Expected behavior

No warning raised when using none for the X-Robots-Tag header.

Installation method

None

Operating system

None

PHP engine version

None

Web server

None

Database engine version

None

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

None

Are you using the Nextcloud Server Encryption module?

None

What user-backends are you using?

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

Configuration report

No response

List of activated Apps

Irrelevant ?

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

No response

[szaimen]

Cc @MichaIng

[ernolf]

While "none" is indeed equivalent to "noindex, nofollow" for Google, but seems to be not supported by Bing and probably other search engines. /pull/36689

[MichaIng]

Also noted in pinged issue for developers and admins: #34692 (comment)

I will never add another admin check change without linking/explaining the reason right within the admin panel, people just keep asking instead of reading 😄. I already have another important change in pipeline regarding the X-XSS-Protection header 🙈.