lifeycle.on_before_unmount()

import joystick from '@joystick.js/ui';

const Index = joystick.component({
  lifecycle: {
    on_before_unmount: (instance = {}) => {
      // Handle the on_before_unmount() event.
    },
  },
  render: ({ state, when }) => {
    return `
      <div>...</div>
    `;
  },
});

export default Index;

on_before_unmount(component_instance: object) => undefined