While using FireFox search tab (for any search engine) after you type the query and hit enter the search result opens up in the same page. Sometimes this is a nuisance when you every time have to open a new tab before doing the search. Here is a solution to this problem.

Temporary:
After you enter the query and FireFox search bar instead of hitting enter hit alt+enter. And you get the search result in new tab.

Permanent:
If you want this to be a permanent feature here are the steps to follow:

1. In FireFox address bar (where to type the website address) type about:config and hit enter.
2. In filter box just below the address bar paste this text: browser.search.openintab (Note: If you see nothing after you paste the above text in filter box then you need to remove the space which is there just after the text you pasted. ???browser.search.openintab ??? as you see (or rather let you cursor tell you that) there is a space after openintab, which should not be there. It should be ???browser.search.openintab??? without quotes.)
3. Click on the only value which is displayed to change it to true. And you are done.