Focus eventsFocus events, such as focus and blur, fire when an element gets or loses focus.widely2015-07-292018-01-29https://w3c.github.io/uievents/#events-focuseventhttps://developer.mozilla.org/docs/Web/API/FocusEventapi.Element.blur_eventapi.Element.focus_eventapi.Element.focusin_eventapi.Element.focusout_eventapi.FocusEventapi.FocusEvent.FocusEventapi.FocusEvent.relatedTargetapi.HTMLElement.blurapi.HTMLElement.focusapi.HTMLElement.focus.options_focusVisible_parameterapi.HTMLElement.focus.options_preventScroll_parameterhttps://nowyoucanuse.com/features--focus-events.html