[Bug]: Notifications in Calendar on the desktop site don't work

⚠️ 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

I enabled browser notification for the website, but I still don't get any notifications about my Calendar events.

Steps to reproduce

1. Create an even with notification
2. Wait for the time of the event start
3. You don't receive a browser notification, even thought browser notification for the website are enabled

Expected behavior

Receive a browser notification

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

No response

List of activated Apps

No response

Nextcloud Signing status

No response

Nextcloud Logs

No response

Additional info

No response

No source files, tests, or entry points are identified in the report. Start by reproducing the missing browser notification for a Calendar event on the desktop site, then trace the notification path; done means the expected browser notification is received at the event start.