Loads forever when clicking on 'Not grouped' with a lot of users.

[razerrazer]

Describe the bug

During a test case with 25,000 test users in our developer build of Nextcloud, we are facing an issue where clicking on 'Not grouped' causes the web browser to hang after a few seconds.

same issue occur with Chrome as well!

Steps to reproduce

1. Go to "Contacts"
2. Click on "Not grouped"
3. See error

Expected behavior

hangs

Actual behavior

hangs

Contact version

7.0.0 and 6.1.3

Operating system

No response

PHP engine version

None

Web server

None

Database

None

Additional info

No response