old_contents: import { createElement, render } from 'preact';
  
  /**
   * @param {import('../../src/index').RenderableProps<{ context: any }>} props
   */
  function ContextProvider(props) {
  	this.getChildContext = () => props.context;
  	return props.children;
  }
  
  /**
   * Portal component
   * @this {import('./internal').Component}
   * @param {object | null | undefined} props
   *
   * TODO: use createRoot() instead of fake root
   */
  function Portal(props) {
  	const _this = this;
  	let container = props._container;
  
  	_this.componentWillUnmount = function() {
  		render(null, _this._temp);
  		_this._temp = null;
  	};
  
  	// When we change container we should clear our old container and
  	// indicate a new mount.
  	if (_this._container && _this._container !== container) {
  		_this.componentWillUnmount();
  	}
  
  	// When props.vnode is undefined/false/null we are dealing with some kind of
  	// conditional vnode. This should not trigger a render.
  	if (props._vnode) {
  		if (!_this._temp) {
  			_this._container = container;
  
  			// Create a fake DOM parent node that manages a subset of `container`'s children:
  			_this._temp = {
  				parentNode: container,
  				childNodes: [],
  				insertBefore(child, before) {
  					this.childNodes.push(child);
  					_this._container.insertBefore(child, before);
  				},
  				removeChild(child) {
  					this.childNodes.splice(this.childNodes.indexOf(child) >>> 1, 1);
  					_this._container.removeChild(child);
  				}
  			};
  		}
  
  		// Render our wrapping element into temp.
  		render(
  			createElement(ContextProvider, { context: _this.context }, props._vnode),
  			_this._temp
  		);
  	}
  	// When we come from a conditional render, on a mounted
  	// portal we should clear the DOM.
  	else if (_this._temp) {
  		_this.componentWillUnmount();
  	}
  }
  
  /**
   * Create a `Portal` to continue rendering the vnode tree at a different DOM node
   * @param {import('./internal').VNode} vnode The vnode to render
   * @param {import('./internal').PreactElement} container The DOM node to continue rendering in to.
   */
  export function createPortal(vnode, container) {
  	return createElement(Portal, { _vnode: vnode, _container: container });
  }
  
new_contents: import { createElement, render } from 'preact';
  
  /**
   * @param {import('../../src/index').RenderableProps<{ context: any }>} props
   */
  function ContextProvider(props) {
  	this.getChildContext = () => props.context;
  	return props.children;
  }
  
  /**
   * Portal component
   * @this {import('./internal').Component}
   * @param {object | null | undefined} props
   *
   * TODO: use createRoot() instead of fake root
   */
  function Portal(props) {
  	const _this = this;
  	let container = props._container;
  
  	_this.componentWillUnmount = function() {
  		render(null, _this._temp);
  		_this._temp = null;
  	};
  
  	// When we change container we should clear our old container and
  	// indicate a new mount.
  	if (_this._container && _this._container !== container) {
  		_this.componentWillUnmount();
  	}
  
  	// When props.vnode is undefined/false/null we are dealing with some kind of
  	// conditional vnode. This should not trigger a render.
  	if (props._vnode) {
  		if (!_this._temp) {
  			_this._container = container;
  
  			// Create a fake DOM parent node that manages a subset of `container`'s children:
  			_this._temp = {
  				parentNode: container,
  				childNodes: [],
  				appendChild(child) {
  					this.childNodes.push(child);
  					_this._container.appendChild(child);
  				},
  				insertBefore(child, before) {
  					this.childNodes.push(child);
  					_this._container.insertBefore(child, before);
  				},
  				removeChild(child) {
  					this.childNodes.splice(this.childNodes.indexOf(child) >>> 1, 1);
  					_this._container.removeChild(child);
  				}
  			};
  		}
  
  		// Render our wrapping element into temp.
  		render(
  			createElement(ContextProvider, { context: _this.context }, props._vnode),
  			_this._temp
  		);
  	}
  	// When we come from a conditional render, on a mounted
  	// portal we should clear the DOM.
  	else if (_this._temp) {
  		_this.componentWillUnmount();
  	}
  }
  
  /**
   * Create a `Portal` to continue rendering the vnode tree at a different DOM node
   * @param {import('./internal').VNode} vnode The vnode to render
   * @param {import('./internal').PreactElement} container The DOM node to continue rendering in to.
   */
  export function createPortal(vnode, container) {
  	return createElement(Portal, { _vnode: vnode, _container: container });
  }
  
subject: Add appendChild shim to Portal