Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, are described for handling input received from a common interface of a program and a runtime environment when both the program and the runtime environment are configured to consume the received input. Given that both a browser program and a media player program hosted by the browser program are configured to detect an event of a certain type, there may be a contention of whether the browser program or the media player program may act first on the detected event. The disclosed systems and techniques enable interpretation of a user's intent when the user interacts with a webpage hosting media content and when the user's input occurs over media content rendered by the media player program. Similar advantages may also be realized within the context of another execution environment, or other program, different than a browser program.