So try to go to "tree" at the bottom of your window and create a new folder (see attached image).
I can't because I think it's a matter of access.
After the creation either the new folder appears at the top, or it appears at the bottom and in this case there will be "just" to deploy the tree tab each time.
You can also add a link to a folder in the Common Folders list from the Folder Tree by right-clicking the folder and selecting Add to common folders from the shortcut menu. You can also remove a link to a folder from the Common Folders list by right-clicking the link and selecting Remove from Common Folders from the shortcut menu. The folder's navigation settings are lost when the cache contents are deleted.
So, basically, you right-click on your directory and then Add to common folders.