More long time in chrome second load

I have checked more and more time my website from more server but i don’t understand because i everytime have more long time in second load with chrome …

Sample checking from frankfurt firefox. 1st load first byte 0.4 … Second load 0.2
When checking from chrome first byte 0.5 second loading 1.8 why this where are the problem for thiss slow loading in chrome ?

Check yourself where are my error?

This from frankfurt …with firefox