This happened the other day at not the greatest time bust suddenly MetaMask was showing a total blank screen and giving me some chrome extension error. I tried to update my browser but then it wouldn't work. I tried to do a system update in Manjaro and more stuff seemed broken. Suddenly I decided to reboot and the thing really wouldn't get past the GRUB which I'm using as my boot loader.
I edited the grub config to go to run level 3 and could at least get to a command line. It was almost like that update messed up the Nvidia drivers. I tried various things but couldn't get it back up.
I bought some new USB flash drives from Walmart and put a new Manjaro iso on one and a Ubuntu iso on another. Both of them did fine but the delima is Manjaro won't let me just update the previous install I had on the one partition. Also I have a dual boot setup even though I never use Windows. I always just kept it just incase there was some program I needed Windows for.
I'm running off other computers right now and I'm not sure if I should just blow everything out and start fresh on the one machine. I would rather be able to get back in my system the way I had it setup but that is looking unlikely.
It seems like other people ran into this same type of stuff when having a failed update in Manjaro.