com.spotify.Client VS com.mojang.Minecraft

There is nothing "unsafe" about flatpak. In fact for every package on flathub you can see exactly what the "unofficial" packagers do in the corresponding github repository. For example here is the repository for Spotify, if you look at the json manifest file you can see they are repackaging the "official" Snap with the necessary libraries and scripts to support it running as a flatpak. Everything there is open source and able to be examined.

If you click on the "Manifest" link for the package on flathub, it will take you to where the code that packages the app resides. There you can review exactly what the packager does in the json manifest. Here's the one for the Spotify client, for example, which shows where it pulls in dependencies and where it downloads the proprietary code from (in this case they base it on the snap) and what commands it executes while packaging the flatpak.

Try installing it via Flatpak

Flatpaks builds are made to be reproducible. Everything is done openly and you can check how the apps like for example Spotify where made.

Why not just use the flatpak?

Judging by the manifest, the Spotify Flatpak is built from the Spotify Snap.

*PSA: it's not actually official!

I always just install the flatpak: https://flathub.org/apps/details/com.mojang.Minecraft

The best launcher right now is Prism Launcher, a MultiMC fork with Curseforge integration that comes pre-bundled with an optimized version of Java when downloaded from flathub (read: the Discover store), but there are plenty of options including GDLauncher, portablemc if you want a command-line launcher, or, heck, the vanilla launcher.

I don't get it what do you want exactly to know? For Steam games you have to use Steam launcher but for Minecraft you have many launchers to pick: original Minecraft launcher (https://flathub.org/apps/details/com.mojang.Minecraft) but I don't recommend it cause it lacks of mod support etc. Best launcher as far for me is Prism Launcher what is for of MultiMC launcher (https://flathub.org/apps/details/org.prismlauncher.PrismLauncher).

Maybe try this Flatpak package.

The official launcher works fine under Linux. It's just a 🥙 to manage multiple modded instances.

If you just want to play Vanilla, then Minecraft is what you're looking for. If you want to play modded, then you should probably use PolyMC instead.

So I would recommend installing PolyMC or Minecraft with Flatpak.

My question is, how to play Minecraft more privately? Now Minecraft = Microsoft. I need a login to their services (Microsoft account is needed), to play Minecraft. The game is available on Flathub and I can combine it with Flatseal. Any more recommendations how to cut-off Microsoft of my Linux machine?