No-Library (pure JS), HTML, CSS, JavaScript
no getElements selectors inside shadowRoot
click events on CE and button inside CE (analyse clickedTarget, currentTarget & composedPath)
Move SVG tags inside Custom Element shadowDOM
walk up the DOM crossing shadowDOM
iconmeister.github.io
test if code works on FireFox, Safari and attributeChangedCallback is triggered.
append() lightDOM content to shadowDOM
.append with document runs disconnectedCallback and connectedCallback again
Inject SCRIPT in execute SCRIPT in shadowDOM scope