When you scroll down the pages and find something relevant on say the fourth page of results, clicking on that link will open the page in the same tab. When you want to go back to the google results page, you will land back on the first page of results and not the fourth (as in the example) on which you found your result.

Of course, holding ctrl would open the result in a new target, but a toggle or setting to open results in a new target would certainly be more efficient.

Thanks for this useful script.