message: fixutils/is): handle elements in an iframe
diff: -import type { Element } from '@interactjs/core/types'
  -
  import isWindow from './isWindow'
  import * as win from './window'
  @@ -17,16 +15,15 @@ const bool = (thing: any): thing is boolean => typeof thing === 'boolean'
  const string = (thing: any): thing is string => typeof thing === 'string'
  -const element = (thing: any): thing is Element => {
  +const element = (thing: any): thing is HTMLElement | SVGElement => {
  if (!thing || typeof thing !== 'object') {
  return false
  }
  - // eslint-disable-next-line import/no-named-as-default-member
  const _window = win.getWindow(thing) || win.window
  - return /object|function/.test(typeof _window.Element)
  - ? thing instanceof _window.Element // DOM2
  + return /object|function/.test(typeof Element)
  + ? thing instanceof Element || thing instanceof _window.Element
  : thing.nodeType === 1 && typeof thing.nodeName === 'string'
  }
  