What are the file types for which Messenger provides preview?

Messenger supports preview of file types only when it is supported by the browser. Each browser has its own set of file types that it can support rendering, so it can vary based on the browser and OS combination.

For example, .mp4 is a standard file type that is supported in all browsers whereas .mov is only supported in Safari and Firefox browsers in iOS. So Messenger uses a browser API to detect if it can support rendering and show preview. If not, it falls back to the download option where the user has to download the file and open in their native app to view. For information about file types preview, see Supported content profiles.