Microsoft patent application shows how it might start using in-game context to show ads.

A system for “contextually aware” ads described in the patent application could pause gameplay “at the operating system level” to show an ad when certain in-game events or triggers happen. For instance, players might get an ad break after a boss fight or when their avatar “is determined to be in a safe location, such as the user’s team base.” [Link: Microsoft Patents "Ad-Credit" System for PC and Consoles to Serve In-Game Ads During Pause Windows | https://respawnfirst.com/microsoft-patents-ad-credit-system-for-pc-and-consoles-to-serve-in-game-ads-during-pause-windows/ | RespawnFirst]