Yandex disk support

Issue is more-or-less already open, waiting for a developer. Progress in Duplicati is volunteer-limited.
Developers are especially encouraged, but volunteering in any capacity will help keep project moving.

Disk WebDAV API looks official. If they’re doing something to slow it down, they’re not talking about that.

Alternatively you can try using Duplicati Rclone storage type with rclone’s config set to use Yandex Disk