One-by-one, remove each user as described in the section «Removing users».
When you remove the last user, the «Disabling directory protection» warning appears. This message reminds the user that removing the last user will disable password protection for the directory. The respective directory (e.g. «html») then becomes publicly accessible.
Disabling password protection for directories
If you want to disable password protection for a directory (e.g. html), double-click to the left of the «pencil icon».
Then click on the «Delete» button to disable password protection for the selected directory, including all users. This cannot be undone.