Middle mouse actually performs a 'quick search', using the field or item you clicked on as the search parameter.
So in your screenshot, if you clicked on '2008' instead, then all tracks in your library from 2008 would be listed.
You can see this in your left side-panel - the 'Search Results' node is highlighted after the middle mouse click.
So your question is, can we open search results in a new tab with a key combination?
The current answer is no, I don't think so (but there is a wish-list forum).
However, if your tab's 'navigation lock' was set to 'full lock', then the search results would open in a new tab, I think.