title: Activity button on ribbon not working
body: <p>For some reason, the Activity button on the ribbon isn't dropping down the list of available activities when I click on it. This happens in both of the forms I have tried it on, Accounts and Service Cases. I get no script errors or any other errors.</p>
  
  <p>Our environment has been updated up to rollup 11.</p>
  
  <p>Is there anyway I can debug what's going on? I can't seem to get very far with the built-in IE developer tools.</p>