I've tried every available Pinboard add-on here and this one is the best so far. It integrates into the searchbar, it has good design, it is lightweight and maintained.

My only gripe is inability to save popup dialog with a shortcut, instead I need to use mouse to click 'Add bookmark' button. This is my feature request to the author: it would be nice to have this great add-on more keyboard friendly in the future. Thanks.