> Certain events, such as clicking or pressing a key, can spawn pop-ups regardless of if the pop-up blocker is on. This is intentional, so that Firefox doesn't block pop-ups that websites need to work. https://support.mozilla.org/en-US/kb/pop-blocker-settings-exceptions-troubleshooting#w_is-the-pop-up-shown-after-a-mouse-click-or-a-key-press > The general rule is that popup blockers will engage if `window.open` or similar is invoked from javascript that is not invoked by **direct user action**. https://stackoverflow.com/questions/2587677/avoid-browser-popup-blockers