document.getElementById('qlist-wrapper').getElementsByClassName('question-summary narrow').toString();

"[object HTMLCollection]"

webView.evaluateJavaScript("document.getElementById('qlist-

wrapper').getElementsByClassName('question-summary narrow').toString();", completionHandler: { (html: Any, error: Error?) in
        print("(html)")
        if let error = error {
            print("(error.localizedDescription)")
        }
    })
}

po html
error: Execution was interrupted, reason: EXC_BAD_ACCESS (code=1, address=0xfffffffffffffff8).
The process has been returned to the state before expression evaluation.

Array.prototype.slice.call(document.getElementById('qlist-wrapper').getElementsByClassName('question-summary narrow'));