Newida rhai safweoedd y canolbwynt i' w ffenestr ei hunain gan ddefnyddio window. focus (). Pery hyn i' r ffenestr ddod i' r blaen gan darfu ar beth bynnag oedd y defnyddiwr yn gweithio arno ar y pryd. Penoda' r dewisiad yma' r ymateb i' r ceisiau hyn.
Some websites set the focus to their browser window on their own by using window. focus(). This usually leads to the window being moved to the front interrupting whatever action the user was dedicated to at that time. This option specifies the treatment of such attempts.