Samsung use (used?) Linux as the base OS for a large number of their TVs so of course replacement firmware projects sprang up (e.g. SamyGo [1]). The project added additional functionality to their TVs like playing movies from a USB stick - features that Samsung had restricted to their higher-end TVs.
Within a few months Samsung had released an ‘official’ firmware upgrade that removed the ability to load unofficial (unsigned I guess?) updates.
