I just want this option to be added to the "Middle-click on empty space"

This makes it as close to standard TAB behavior in browsers as possible. In firefox by default, when middle-clicking on empty space, a new tab is created. When middle-clicking on a tab, the tab is closed. This has a nice balance and is easy to understand.

Firefox can also be made to duplicated a tab when middle-clicking the empty space. This is as close to opening a new tab as one can get with the taskbar because there is no "empty task" to open. So to make the taskbar items consistent with the way most browsers work with tabs, I suggest that middle-clicking the empty space opens a new instance of the program. This works really well with the option to close the program by middle-clicking.

I've read through four pages of similar suggestions and didn't see this one. It seems super obvious when you think about. Please implement this...

Thanks for such a great program. The middle-click to close is the main thing I use it for and it works great!