Minetest is a free open source alternative to Minecraft. The official account is:
You can also follow a Minetest world building project called Illuna:
There's also an unofficial Minetest video channel:
The actual Minetest app is available for Windows, Mac, Linux, Android and BSD from the official site at https://www.minetest.net/
Videos about Minetest
Fosstodon is an English speaking Mastodon instance that is open to anyone who is interested in technology; particularly free & open source software.