title: Caching a page where the header shows user details
body: <p>We have a website that is using CodeIgniter and is using the full page caching technique:
  <a href="https://www.codeigniter.com/user_guide/general/caching.html" rel="nofollow">https://www.codeigniter.com/user_guide/general/caching.html</a></p>
  
  <p>The problem we have is on the main header (navigation) of the website we either have (login/register) buttons or if the user has logged in we show the picture of the user with his/her name and a dropdown to edit profile and logout.</p>
  
  <p>The cache right now caches the information generated by the user who activated it and therefore even if you are logged in or not it shows that.</p>
  
  <p>How does one achieve caching a page but display some areas according to sessions?</p>
  
  <p>I understand "ajax" is one way of achieving it, but is there another way? A more correct way to do this?</p>