Guardian to consider preventing access to content if ad-blocking proliferates

David Pemsel, chief executive of Guardian Media Group, says newspaper is undertaking testing of pop-up message asking readers to switch off ad-blockersThe chief executive of the parent company of the Guardian has said the newspaper would consider preventing readers from accessing its content if take-up of ad-blocking software becomes widespread.David Pemsel, the chief executive of Guardian Media Group, would not be drawn on the rate of ad-blocking among Guardian readers, but acknowledged that th