KMS for Intel graphics

Some time ago I uninstalled the xf86-video-intel to resolve randoms freezes of X.org. Now I have the suspect that I have a half-configured system because reading the page of the ArchWiki about Intel graphics in Italian and then the one in English I noticed that there are no modules in /etc/mkinitcpio.conf.
Did I need to activate some kernel’s option/module?

That controls what you are loading in the initramfs which is what it loaded before the actual system. You shouldn’t need to change that unless you have specialized needs or something is not working as it should.

I noticed that when I play a video in firefox, for example on youtube, there is a screen tearing effect. Same thing while playing Wakfu. I’m afraid this is caused by a misconfiguration of the kernel modules that control the integrated GPU.