I have 3 websites configured identically here on cloudflare. Flexible SSL, always use and rewrite HTTPS.
.htaccess are the same for all 3 websites. No rewrite rule in the .htaccess.
By refreshing the browser (F5) everything is fine: SSL is working.
But, by a forced refresh (Ctrl+F5) one page is connected by SSL but 2 are connected by HTTP. After pressing F5 https is working.
Anyway, everytime a forced refresh is switching to http.