_onFocusIn(e) {
    const {
      template
    } = this.pswp;

    if (template && document !== e.target && template !== e.target && !template.contains(
    /** @type {Node} */
    e.target)) {
      // focus root element
      template.focus();
    }
  }
Trap focus inside photoswipe

@private
@param {FocusEvent} e