https://developer.mozilla.org/en-US/docs/Web/API/CustomEvent
CustomEvent - Web APIs | MDN
The CustomEvent interface can be used to attach custom data to an event generated by an application.
web apiscustomeventmdn
https://caniuse.com/?search=ciu/customevent
"ciu/customevent" | Can I use... Support tables for HTML5, CSS3, etc
can i usesupport tableshtml5 css3customeventetc