I love the "duplicate tab" add-on, a abandoned plug-in develoved in 2007. It's a very simple add-on, their few characteristics already are including in "Multiple Tab Handler", except the duplicate-tab icon relocatable in the navegation bar. This icon is vital for me.
Can yours integrate an icon that allows the same?
I would change of addon and recommend it.
Thanks for its attention.
Actually MTH includes "duplicate tabs" feature, but it is focused to duplicate "multiple tabs", instead of "duplicating". Such toolbar button is out of purpose of MTH.
However, I think MTH should work with any other addon provides such toolbar button. (For example, if you click the button with selected multiple tabs, then the button should duplicate all of selected tabs.) I'll update MTH for the addon when you tell me it.