I use Manjaro with the Cinnamon DE. For a while now, I have the issue that my computer randomly restarts. Furthermore, when I play games, or when I perform certain actions on Firefox, the screen turns black for a few seconds, and sometimes even indefinitely.
I did some investigating, and it appears that Manjaro switched from Xorg X11 to Wayland.
If that is the case, that must be what is causing the issues. How can I check if Manjaro is running Xorg or Wayland, and how do I revert to Xorg?
Manjaro didn’t do anything itself, upstream projects like GNOME and KDE Plasma did. Cinnamon only has experimental Wayland support and X11 is still default.
XY Problem detected: You’re asking about your attempted solution rather than your actual problem. This leads to enormous amounts of wasted time and energy, both on the part of people asking for help, and on the part of those providing help.
Please see:
P.S.: I’m closing your previous thread since you never returned.
you can try xlibre which a replacement for xorg.
@Arikania both @Yochanan and @robin0800 are your best options. The Xorg should no longer be used, the Xorg team has for all intents and purposes abandoned Xorg.
Wayland is actually very stable on Cinnamon, there are a few quirks, like tool tips on some Applets showing on other side of screen etc, but as far as once can say that Wayland is ready you could use it daily, as long as your apps don’t require X11.
Which brings to Xlibre, if you need X11, just add the repo for X11 and follow their instructions, it has been working flawlessly on Cinnamon.
Last but not least, you stated that you have been using Cinnamon for a while, you have to keep the Applets and Extension updated, which can cause things like you are describing, see this thread: How to prevent desktop crashes in Cinnamon
Cheers,
-John
Wayland does support X11 applications via its XWayland subsystem. 
@Aragorn That is true, not all but most. Rustdesk for example cannot run in unattended mode (as a service) and also Vokoscreen is not in feature parity with it’s X11 counterpart because Wayland does not support those features yet.
I am starting to see Cinnamon as the one OS that can be for those that want to run one or the other when ever they want, true choice.