Total Commander

Draging and dropping a tab allows to rearrange tabs in the same panel or make a copy in another panel.
Consistently with file operations, it might be possible to extend the function.

Shift-drag to move to a desired place in another panel.
Ctrl-drag to make a copy to a specific place in the same panel.

Thanks for your suggestion. Currently you can double click behind the tabs to duplicate the current tab.

Thanks for the hint.
I wish it somehow could be used when tabs were hidden; but there was no simple solution so far.
Hence, an additional button with cm_OpenNewTab command or Ctrl+T are used for now.