Hello, 
I worked with PW 2.6.15 dev and I've just updated to 2.6.22. 
My templates are configured with a cache enabled. When I update a page content, visitors don't see any change, I see my changes just if i'm logged. I understand that the cache is used only for guest, it's my choice in the configuration panel (guests only). 
It's not a problem of  navigator cache, i have disabled it for my tests. 
But how to make the page cache cleared when I save my page?  
Thanks for your help.