This is a chrome issue and it seems some string is missing in Autoptimize. When I inactivate Autoptimize the problem seems to be gone.
When loading the pages first time in Chrome the fonts is changing (jumping) and then the page looks normal after the first load.
I dont know how to fix this properly and/or if its Chrome or Automtimize that is missing someting but I found a thread discussing this issue:
https://productforums.google.com/forum/#!topic/chrome/elw8busIfJA
PS! Copy complete link above to find the thread