Summary:<p>A/B test on subtopic pages was performed for a few months.<p>- Existing subtopic pages with expanding sections ('show or hide' or accordion control)<p>- Alternative subtopic flat list with subheadings and dividers to organise the content<p>Half of the people who visited the subtopic pages saw the accordion design, while the other half saw the newer list design.<p>The data showed quite clearly that the list design performed better, for both desktop and mobile users.