Are you looking for an easy way to duplicate tabs in Firefox? Now you can add the ability to duplicate those tabs with a single right click using the Simple TabCopy extension for Firefox.
To duplicate a tab right click somewhere within the browser window area and select Duplicate Tab. Keep in mind that the feature is not available when right clicking on the tab itself…
Note: Works with Firefox 2.0 – 5.*
Download and Install the Simply TabCopy Extension [Mozilla Add-ons]