Modified date of shared documents


I’m doing backups via webdav of some folders in my nextcloud. I recognized, that some documents are not backuped if they were modified. Those documents are shared by someone else. The modified date of those documents does not change, if I modify them.

Bug or feature?


Nextcloud version:  19.0.5: 
Operating system and version: Ubuntu 20.04
Apache version:, Apache 2.4.41
PHP version: 7.4