I have a hopefully rather simple Javascript question for you. I have a scrollable, static page which can show/hide a full frame overlay (hiding the whole page) using z-index. When the overlay is shown I create a new event listener to "keydown" in which I for example check for "ArrowDown". When the overlay is hidden, the listener is unsubscribed.
This works beautifully, except that the page below the overlay keeps scrolling up and down as it normally would. I thought I could stop that by using
event.stopPropagation()
which, however, does not help. How can I approach this?