Slightly purple comb tips on cockerels

[Cheekychook12]

I have two cockerels who have slightly purple comb tips, no signs of respiratory or any other kind of distress, they seem perfectly healthy
What might this be?
I just posted the one with the most obvious purple
Edit: it’s currently summer so I know it’s not frostbite

 

[Wyorp Rock]

Looks like it may have been nipped or bitten by another bird.

If he's acting fine, I wouldn't worry too much about it.