The Projects tree organizes Projects by grouping them into folders. Each Project or folder can be deleted or modified as necessary.
The creation of a new Project is explained here. To create a new folder, click New and then Folder on the Ribbon - Home tab.
Subsequent operations require selection of the desired Project or folder. It is possible to select multiple Projects or folders at once holding down Ctrl or Shift keys while selecting them with the left mouse button.
You may also move any Project or folder to another location using drag-and-drop.
Clipboard operation are useful if you want to transfer a Project to another computer - copy it to clipboard, paste to some text file (e.g. using Notepad), transfer the text file to another computer and then paste the Project into Portable Offline Browser. You can also paste Project into the File | Templates window to create a new Template based on the Project settings.
The last Delete operation can be undone using the Undo button on the Quick Access toolbar.
To create nested folders, use the Ctrl key. For example, to create a new folder inside of an existing one, select the folder, then click New on the Ribbon - Home tab, hold down the Ctrl key, double-click on the New folder and then release the Ctrl key.
You may also drag and drop one folder inside of another by holding the Ctrl key while dragging the folder
To expand or collapse all folders please use Ctrl [Numpad+] and Ctrl [Numpad-] keyboard shortcuts respectively.