[Bug]: No user error for failed drag-and-drop or file upload error

[ChristophWurst]

⚠️ 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

Sabre currently throws a forbidden exception when uploading files into Files. This probably comes from some other testing, but it means uploads don't work.
If I now try to upload via the + button or drag-and-drop, the console shows an error, but the UI doesn't. If I don't look at the file list as a user, I might think my file is uploaded.

no-upload-error-feedback-2023-11-16_11.48.11.mp4

Steps to reproduce

0. Have a broken home directory, or be out of quota, I guess
1. Upload a file

Expected behavior

An error toast or something similar

Installation method

None

Nextcloud Server version

28

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

No response

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

No response