What is a quick way to duplicate a tab in Safari?

Safari 13.1 finally added Duplicate Tab functionality, in both the contextual menu on tabs and in the Window > Duplicate Tab menu.

It doesn't come with a keyboard shortcut by default, but you can create your own keyboard shortcut in Keyboard preferences. (Internet Explorer, where this feature seems to have originated, used ⌘ + K.)

I have two alternatives:

1. Press Cmd+L (go the Location/Search field), then Cmd+Return.
2. Click the back button (<), then press Cmd while clicking the forward button (>).

Both of these will open a tab in the background. (Often, Cmd + click opens the click target's reference in a new tab.)

If you also press Shift while performing the second step of either of these alternatives, the tab will open in the foreground.