Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for context-adaptive scanning of digital components. In one aspect, a method comprises: selecting a given digital component from among a plurality of digital components based on a current scanning priority of the given digital component; scanning the given digital component, comprising determining a current state of the given digital component; determining a current context of the given digital component based on one or more of: (i) the current state of the given digital component, or (ii) a current scan index of the given digital component that specifies a number of times the given digital component has been scanned; determining an updated scanning priority of the given digital component based on the current context of the given digital component; and re-scanning the given digital component according to the updated scanning priority.