How do I access snapshots with Webdisk?

You can access snapshots via Webdisk using a little trick. In Webdisk, select the folder where the desired file resides. With a right mouse-click, select "Anzeigen und editieren", "Link zu Datei / Ordner".

This gives you a direct link to the folder. Open a new browser window, enter this link in the address bar and then add "/~snapshot" to the end of the address. This opens a folder containing a list of all snapshots.