Your understanding is correct. The scrolling away from the viewport is not the problem, but rather the fact that the virtualization mechanism removes the element once it is no longer visible.
Once this happens, the browser will emit subsequent keyboard events from the document element.
Thank you again for clearing up my understanding, Petyo :)
We're a place where coders share, stay up-to-date and grow their careers.
We strive for transparency and don't collect excess data.