Test pre-requisites Add the Online Users block Connect simultaneous with other accounts so that you can see something in the block Use all the major browsers to test this issue Test steps Check for consistency in the block styles, CSS, icons, etc... Go to Home ► Course ► Reports ► Course participation Make a search so that you have results Hack user/message.html:46 (right before `if (!empty($error))` and set $error to something. Now select a bunch of users and "Send a message" You should see an icon next to the list of users, make sure it appears nicely Revert your hack and make sure it still look nice I didn't find a quick way to display this icon without hacking the code