Web Components Issues

[caridy]

This issue is a placeholder to hold back references to things that are important to track outside of this project:

MutationObserver's connect and disconnect

• Backpointer: Make it possible to observe connected-ness of a node whatwg/dom#533
• Status: under discussion
• Use-case: today we can't rely on Custom Elements because of the global registry, instead we patch the DOM methods to detection insertion, but that's not reliable enough.

Event and CustomEvent extensions

class FooEvent extends CustomEvent {
  constructor() {
    super('foo');
  }
};
var foo = new FooEvent();
console.log('This evaluates to "false" which is unexpected', foo instanceof FooEvent);
console.log('This evaluates to "true" which is expected', foo instanceof CustomEvent);
console.log('This evaluates to "true" which is expected', foo instanceof Event);

• Safari: https://bugs.webkit.org/show_bug.cgi?id=188083
• Edge: https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/11923584/ and https://developer.microsoft.com/en-us/microsoft-edge/platform/issues/12081372/