_Auster_: Thronebreaker: The Witcher Tales
tl;dr: it adds DRM'd bundleware to your account (GWENT base game + some extras for GWENT) and Thronebreaker and GWENT might communicate to do some form of validation (aka "DRM"). The second part still needs confirmation.
From the store page:
How about more GWENT extras?
Unlock 20 cards (standard versions) for use in GWENT: The Witcher Card Game and search for their exclusive premium versions during your travels in Thronebreaker.
Note: Standard versions of the 20 cards can also be crafted directly in GWENT: The Witcher Card Game.
And the system requirements put salt in the burn:
Note: Owners of Thronebreaker: The Witcher Tales will get GWENT: The Witcher Card Game added to their library.
Also this appears right below the "how about more GWENT extras" part, which makes it sound like, besides adding DRM's contents to your account, the game has some form of DRM as well:
Make sure to launch Thronebreaker first in order to claim the in-game bonus items in GWENT
I don't have the game myself, so I can't confirm this last part.
That does not sound like DRM, but more like a goodie? As long as it does not restrict you from any features in Thronebreaker, it does not equals to DRM, at least from my understanding. Comparable with some games, which enable some small goodies, if they detect their prequels installed on your machine (e.g. Borderlands 2 with their BL 1 skins).