Finally true, native, "duplicate tab" functionality for Google Chrome with a customizable keyboard shortcut. This extension also includes an options page and built-in documentation.
Installing this extension will enable you to set a keyboard shortcut of your choice that will duplicate a tab in Google Chrome – not just opening a new tab with the same URL – but the true functionality that also duplicates the tab's history and all other attributes without requesting a page-reload / page-refresh.
You must have Google Chrome version 25.0 or newer in order to use this extension. You can update Google Chrome by going to the "About" page.