I have a laptop with Liunx Mint 18 and have this problem with this game, when I play others games, for example, CSGO, Half Life 2 o Portal 2 doesn't have this problem. I don't understand what can happen

Thanks :)

A late thanks from me, too!

It's still appreciated even if late ;P
But of course it's Daniel Scharrer who actually deserves these thanks.

The bug affects shadows on all Radeon cards, I think. It certainly is present on my Steam Deck. Sadly this hack no longer works on modern Linux, seemingly as it depends on an undocumented function in glibc called "__libc_dlopen_mode" that is not available in newer versions. Probably the only workaround now (short of having the expertise to rewrite the graphics override hook in the above hack) is just to run the Windows version through wine, unfortunately.