title: How to elevate collapsing toolbar above main layout like the floating button?
body: <p>How can I set my collapsing toolbar above the activity layout ? </p>
  
  <p>I want to "elevate" it like the floating button. I have tried to set an elevation on the appbarlayout, even on the collapsing toolbar but it doesn't work.</p>
  
  <p>How can I do this ?</p>
  
  <p>Thanks</p>