Test #1: Extant behaviour : Install a supported screen reader such as NVDA. Enable developer mode on your server and make a test course of size S or M. Go to the forum and open a discussion. With your screen reader turned on, mouseover one of the user pictures in the discussion. Observe that your screen reader says "Picture of <user name>". Inspect the user picture you've mouseovered. Observe that it does not have role="presentation" or aria-hidden="true" set. Test #2: New functionality : Edit login_info or some other renderable with access to the $USER global, and add two calls resembling the following: user_picture($USER, array('visibletoscreenreaders' => false)); $foo = new user_picture($USER); $foo->visibletoscreenreaders = false; $OUTPUT->render($foo); Mouseover the two new user pictures with your screen reader turned on. Observe that the screen reader ignores the pictures. Inspect the user pictures you've mouseovered. Observe that they do have role="presentation" set on the img tags, and role="presentation" , aria-hidden="true" and tabindex = "-1" set on their enclosing a tags.