How to execute a script when the custom element is upgraded

Question

I have defined a custom element and I want to execute a script only when the custom element is upgraded to its registered type. The use case is that I must call a custom met

Answer 1

Load the dependency via an import in your custom element module. For example, a custom element module (e.g.something.mjs) which depends on Highcharts:

import '/node_modules/highcharts/highcharts.js'

class Something extends HTMLElement {}

customElements.define('x-something', Something)