darkfish [1] filed a deletion request for nextcloud-app-whiteboard-
integration [2]:

The upstream app seems to have been abandoned, with no update since
[2022/08/31][1], almost 2 years ago. Last release was for [Nextcloud
25][2]. There are user reported issues ([3] [4]) regarding such
abandonment too.

[1]:
<https://github.com/nextcloud/integration_whiteboard/commits/master/>
"Last GitHub Commit"
[2]:
<https://apps.nextcloud.com/apps/integration_whiteboard/releases?platform=25#25>
"Whiteboard Integration Releases"
[3]: <https://github.com/nextcloud/integration_whiteboard/issues/54>
"Issue#54 Switch to an actively maintained whiteboard solution"
[4]: <https://github.com/nextcloud/integration_whiteboard/issues/48>
"Issue#48 Is this integration dead?"

[1] https://aur.archlinux.org/account/darkfish/
[2] https://aur.archlinux.org/pkgbase/nextcloud-app-whiteboard-integration/