findAll (cssSelector) { // eslint-disable-line no-unused-vars
    /* istanbul ignore next */
    throw new Error(NOT_IMPLEMENTED)
  }
Find all descendant elements matching the given CSS selector.
*Attention**
    This method is currently not implemented for {VirtualElement}.
    This means you can use it only in importer implementations, but not in render or exporter implementations.

    @param {String} cssSelector
    @returns {Array<DOMElement>} found elements