Custom Files and Folders - Directory not available to select

When attempting to select a custom folder for cleaning, the directory in question does not show up in the tree.

The folder is visible in Windows Explorer (non-hidden / non-system object).

Therefore, why is it not shown in the CCleaner selection modal?

C:\Users\SomeUser\Documents\
Dropbox

On a related subject, why does CCleaner not allow the user to paste or type the path? Having to use a tree selection is like being back on Windows 95.

Thanks.

You may have to logon as SomeUser to be able to clean the Dropbox folder.