How to detect when Mapbox/Leaflet enters or exits fullscreen mode - leaflet

Question

How can I detect when Mapbox or Leaflet enters or exits fullscreen mode?
I found this answer where someone said this:
Documentation says:
map.on('fullscreenchange', function () {
if (map.isFullscreen()) {
console.log('entered fullscreen');
} else {
console.log('exited fullscreen');
}
});
If doesnt work, use this instead:
map.on('enterFullscreen', function(){
});
map.on('exitFullscreen', function(){
});
I tried that, as well as a few variations of the event type parameter. No dice.
Also, the documentation doesn't mention an event for this.
Note that I am using Mapbox GL JS.

Answer 1

I know this is a late response but to anyone in the future this is how I approached it (for mapbox GL JS (without leaflet).
map.on("resize", () => {
if (document.fullscreenElement) // do something
});
You can give the map wrapper div a name and exclusively also check if the map is what triggered the fullscreen event
map.on("resize", () => {
if (document.fullscreenElement?.attributes.name.value === "mapWrapper") // do something
});
And if you are using React you can use a state to hold this information.
const [isFullScreen, setIsFullScreen] = useState();
...
map.on("resize", () => {
setIsFullScreen(
document.fullscreenElement?.attributes.name.value === "mapWrapper"
);
});
...
if (isFullScreen) //do something

Answer 2

This is actually really simple. You don't need anything from Leaflet or Mapbox. Just use an event listener on the document object.
let fullScreenChange;
if ('onfullscreenchange' in window.document) {
fullScreenChange = 'fullscreenchange';
} else if ('onmozfullscreenchange' in window.document) {
fullScreenChange = 'mozfullscreenchange';
} else if ('onwebkitfullscreenchange' in window.document) {
fullScreenChange = 'webkitfullscreenchange';
} else if ('onmsfullscreenchange' in window.document) {
fullScreenChange = 'MSFullscreenChange';
}
function onFullscreenChange() {
// Your stuff.
}
window.document.addEventListener(fullScreenChange, onFullscreenChange);