Even though the drop-down will suggest you "switch to tab", you can open the page in a new tab by Ctrl+clicking that item in the drop-down. Or, if you are viewing that page, you can click in the URL and press Alt+Enter.

Does either of those work for you?

(Some sites may not work correctly when opened twice, but that's a different issue...)

You can use the Cursor Right key to copy a highlighted item from the drop down list to the location bar and use Enter to open that page in the current tab or Alt+Enter to open the page in a new tab.