Screenshot Watermarking

Datadog introduced a steganography-based system to embed widget metadata within screenshots. This system allows for the invisible encoding of a Redis cache key into the pixel data of a widget's border. When a screenshot is taken and pasted, the embedded key can be used to retrieve the original widget's metadata from Redis, enabling features like live previews and context preservation even when users opt for screenshots over direct sharing links. The implementation involves compressing and encoding metadata into an 8-byte key, which is then embedded into the 1px border of a widget. This key is used to retrieve the full widget definition from a Redis cache. The system handles over a billion widget renders per day and ensures collision-free watermarking by prepending organization IDs to widget IDs. Performance optimizations allow for rendering over a billion watermarks per day without impacting app responsiveness.