Turns out that Cyberpunk 2077: Phantom Liberty is hiding a little reference to The Witcher 3, and one that should be music to your ears.
Some mild, fairly early spoilers for Phantom Liberty ahead!
It just seems like CD Projekt Red can't help but reference itself. There's already a Witcher reference in Cyberpunk in the form of an arcade game called Roach Race, but that one's in the base game. However, as spotted by IGN, it seems that there's a brand new reference to be found in Phantom Liberty. It can be found after a certain point during the mission Lucretia My Reflection, when you're guided to a wall-mounted phone in an abandoned building, the main purpose of which is to get in contact with Solomon Reed.
It seems like CD Projekt Red has snuck in Idris Elba's character in Cyberpunk 2077 elsewhere in the game before you even meet him in the DLC.
Now that it's finally out, Phantom Liberty has introduced us all to Solomon Reed, a secret agent deep undercover. But as spotted by some fans online, it looks like you can come across Reed before you even get to the DLC itself. A player shared a screengrab to the game's subreddit, which you can see below, of a character that really looks like Reed, or more specifically Elba. For one, it really does look like Elba, but more importantly his cyberware matches up exactly to how Reed's does when you meet him in the DLC.
Even more importantly than that, though, is a bit of dialogue from Reed that goes into what he does in his spare time. As you're playing through the DLC, at one point Reed will mention that he works as a bouncer at a club in Night City, so it does track even further that it's him. Others have even apparently spotted him elsewhere, like at a bar called Malted Iguana Liquors, but it's worth noting he isn't always there.