[Bug]: TypeError: Cannot read properties of undefined (reading 'from'

[enjeck]

⚠️ 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 OR Nextcloud Community Forum (I've searched it).
• Nextcloud Server is up to date. See Maintenance and Release Schedule for supported versions.
• I agree to follow Nextcloud's Code of Conduct.

Bug description

Cypress tests started failing in Tables, due to "TypeError: Cannot read properties of undefined (reading 'from'". I believe it stems from the code line https://github.com/nextcloud/server/blob/master/core/src/utils/RedirectUnsupportedBrowsers.js#L36

const base64Param = window.Buffer.from(redirectUrl).toString('base64')

I believe that Nextcloud crashes when attempting to redirect an "unsupported" browser because it relies on window.Buffer, which may not be available in Cypress

Steps to reproduce

1.Use a browser or environment (like Cypress headless) with a User Agent not in the supported list.
Navigate to any Nextcloud page.
2. The application crashes immediately.

Expected behavior

No crashes

Nextcloud Server version

master

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

List of activated Apps

Nextcloud Signing status

Nextcloud Logs

Additional info

No response

[joshtrichards]

Maybe drop Buffer in favor of TextEncoder+btoa (with a check it is available just in case) + a fallback for really legacy browsers that uses btoa+unescape+encodeURIComponent?