Publisher Electronic Arts (EA) made the announcement via a blog post. The decision came as a response to requests for mod support for the two games from the community. A spokesperson said that, with mod support, players will be able to make custom maps, units and gameplay logic, in addition to things like replace art and edit data.
— Official CnC (@OfficialCnC) May 20, 2020 The open source assets also mean that mods can be made to work with both Steam or EA Origin launchers. That being said, acquisition of mods will work differently depending on which launcher you use to get them. The ones on Steam can be obtained from its community hub. On Origin though, you can get maps while in the game itself, but you’ll have to install mods manually. Overall, this is good news for fans of the Command & Conquer series, and especially those of Tiberian Dawn and Red Alert. (Source: EA)