Dude there was an article (on this site I think) about this, the F-35 has the hottest engine on the…
Mohsin E.
1

No, it doesn’t as much as the Raptor.

But it won’t ever be fighting Raptors.

The question is; is does it have a lower IR signature than it’s rivals.

The mk1 human eyeball suggests that it will…. I mean, just look at nozzle visibility!

https://basicsaboutaerodynamicsandavionics.files.wordpress.com/2016/03/visual.jpg

The only article on WiB I can see mentioning it is this:

Which offers no actual data & is just conjecture.