When Deus Ex: Human Revolution first released it had a distinctive gold filter that made everything shine like it was covered in Ferrero Rocher wrappers. It was a divisive feature, with some saying the black-and-gold palette was a valid artistic choice and a distinctive look. Others said it made everything look like it was made of bumblebees.
When the director's cut came out, initially as a WiiU exclusive (a fact I'd forgotten until today), the gold filter had been cut and it remained absent on the PC version. Until now, when a modder known as Silent put in the work to restore it.
You may know Silent for his patches to games like Scarface and the early 3D GTA games, focusing on the graphical glitches and timing bugs that occur when these games are played on modern machines. He also contributed to the Silent Hill 2 Enhanced project.
As you can see on his blog about the subject, getting a version of the gold filter working in Deus Ex: Human Revolution—Director's Cut wasn't as simple as flipping a switch marked "make it all shiny". A bunch of changes happened to the lighting between the two versions, and Silent's patch also works at fixing some of those that obviously seem like mistakes.