Complex sentence: The two video codecs are the lossless FFV1, and the lossless and lossy Snow, the development of which has stalled, while its bit-stream format has not been finalized yet, making it experimental since 2011.
Split into simpler sentences: The two video codecs are the lossless FFV1, and the lossless and lossy Snow codec. Development of Snow has stalled, while its bit-stream format has not been finalized yet, making it experimental since 2011.