Use the CloseWatcher API to track native modal closes in GA [🟥 awaiting full support]

[chrisblakley]

CloseWatcher API documentation:

• https://html.spec.whatwg.org/multipage/interaction.html#the-closewatcher-interface
• https://close-watcher-demo.glitch.me/

Here is an example of how to use it:

Probably something like this:

const watcher = new CloseWatcher();
watcher.addEventListener('close', function(){
    //Send GA4 event here for element close
});

[chrisblakley]

https://caniuse.com/mdn-api_closewatcher

Waiting for Safari and Firefox support, but would not be hard to add this inside of a conditional that gets removed when it is fully supported, so not necessarily needing to wait...