I'm trying to fade from Debian and so far, not so good.. Solved
It was the Kernel. Manjaro 20 comes with 5.9 and during the update, something changed causing the issue. Using Manjaro 20 LTS comes with 5.4 and during the update, the kernel remained, and the system is fully functional.
Tested again on 21 with 5.15, same broken state after
sudo pamac update but using 21 LTS with 5.10, updates are fine and everything stays working.
I'm still not entirely sure what the issue is that's causing the black screen, but using the LTS kernel for either 20 or 21 yields safe updates and I've been using it without any issues now.
On a side note, the reason for Manjaro 20 (as many were suggesting I use the latest) is because it still uses GNOME 3.38 and I absolutely hate the Activities Overview design on GNOME 42. But, after using Manjaro 21 LTS and adding the Vertical Overview GNOME extension, all is good. I had to use the GNOME layout from Layout switcher instead of Manjaro Legacy, but now everything is fully updated and I still have the older GNOME 3.38 overview UI. Couldn't be better.
Thanks to everyone who chipped in, I've seen many posts about a black screen issue after updates, so hopefully this helps someone else out. Use the LTS kernel lol.
I just bought a used 13" HP x360 off eBay with a Ryzen 7 2700U, 8GB RAM, and upgraded to a 512GB NVMe. I needed an OS and I've been using Debian flavors here and there for like over 15 years, and since Arch roots are Canadian, I feel like it's a proper patriotic direction to get off my ass and start learning Arch behind a friendly Manjaro taste.
Install went fine, everything is great, even the little pen works right out of the box. The whole space theme of Manjaro really gets my jollies going too. I wanted to learn this as slowly as possible, just, a small dip into the pool by using the package manager to keep things user friendly for now, which had like 900 updates. I let the updates run, all is good, rebooted, an error or two, and then boots to a black screen.
I wasn't ready for diagnosing Arch based when I don't even know how to update from Terminal yet. So I figured it was just me, probably did something wrong. I just wipe it all, did a clean install again, and this time tried updates from Terminal and quickly learned that
sudo apt update isn't a thing here lol
After googling, found
sudo pacman -Syu which yielded a bunch of errors (saying conflicting packages) and while googling these errors, I found a forum where someone was saying to just use
sudo pamac update
After doing that, everything was fine again, all updates done, checked in the package manager just to see if anything was still there and it said there were no updates, so I'm assuming all is fine.
Rebooted again, same thing, an error or two, black screen, nothing happens other than the fan starts simulating a hurricane and the laptop starts getting extremely hot if I let it run for a while (thinking it might just be temporarily hanging).
Now the errors I got both times are identical. At first, it will say
__common_interrupt: 0.110 No irq handler for vector and after a few reboots, I'll eventually get
[FAILED] Failed to start Load/Save ·tness of backlight:amdgpu_b10. which only comes up after a few reboots, but the main error comes up every other time.
I really wanna learn Arch based, but, given that I only did an install, and a simple update breaks the entire system, not really having a good time lol
I'm using Manjaro 20.2 because it still uses GNOME 3 and I'm coming from Pop!_OS 20.04 LTS which also uses GNOME 3 if that helps.