rclone: cmount: failed when host.Unmount in macOS 11 Big Sur and rclone hangs for long time

What is the problem you are having with rclone?

cmount: failed when host.Unmount in macOS 11 Big Sur and rclone hangs for long time

What is your rclone version (output from rclone version)

osxfuse: 3.11.1

rclone v1.53.3
- os/arch: darwin/amd64
- go version: go1.15.4

Which cloud storage system are you using? (e.g. Google Drive)

Nextcloud WebDAV

The command you were trying to run (e.g. rclone copy /tmp remote:tmp)

rclone cmount the-name:/ ~/mnt/test

A log from the command with the -vv flag (e.g. output from rclone -vv copy /tmp remote:tmp)

2020/11/25 13:45:42 DEBUG : /: Getattr: fh=0xFFFFFFFFFFFFFFFF
2020/11/25 13:45:42 DEBUG : /: >Getattr: errc=0
2020/11/25 13:45:42 DEBUG : /: Access: mask=00
2020/11/25 13:45:42 DEBUG : /: >Access: errc=0
^C
2020/11/25 13:45:47 INFO  : Signal received: interrupt
2020/11/25 13:45:47 DEBUG : Calling host.Unmount
2020/11/25 13:45:47 DEBUG : host.Unmount failed
2020/11/25 13:45:47 DEBUG : vfs cache: cleaner exiting
2020/11/25 13:45:47 INFO  : Exiting...
2020/11/25 13:45:47 DEBUG : webdav root '': Destroy:
2020/11/25 13:45:47 DEBUG : webdav root '': >Destroy:
^C^C^C^C^C ( no response)
( after long time, rclone ends without any more outputs. )