## Live sample https://jsbin.com/xibohon/3/edit?html,console,output ## Steps to reproduce 1. create custom element with a child: `<my-element><div></div></my-element>` 2. define this custom element: - on constructor create shadow root, with default slot, - attach `slotchange` event listener 3. observe `slotchange` callback execution. ## Expected result `slotchange` callback is called after `connectedCallback` This is how it works in Chrome 69.0.3497.100 and Firefox 63. ## Expected result `slotchange` callback is not called