Create New Tab
Select 'Create New Tab' from the File menu.
A new tab will be created named 'New Tab'.
The tab will be selected and will be in rename state. You may change its name immediately.
Rename Tab
Select 'Rename Tab' from the File menu.
The currently selected tab will be switched to rename mode.
Change its name and press 'Enter' to accept the change.
Delete Tab
Select 'Delete Tab' from the File menu.
A message box will appear asking you if you are sure that you want to delete the current tab including all the tasks contained in it.
Click 'Yes' if you are sure.
You will not be asked if the tab is empty.