The ability to copy-paste tabs would greatly accelerate my workflow. Instead of copying links and then pasting them into new tabs, I could copy the tab and have two versions of the same tab to work from (e.g. explore different search results within those tabs, or have different text highlights on articles). At the moment, the copy/paste functions are triggered with command+C/V and the copy/paste options are available in the edit menu, but these functions don't do anything. Screen recording below for reference.
If this were to be implemented, it would also be good to make it compatible with a potential bulk-tab selection feature: #411 (Select multiple tabs for bulk ops (horizontal and vertical))