hello,
i installed manjaro 20.0.3 genome version.
after the installation i update the repositories (around 400 number and 900 mb size)
when i reboot my laptop after that process the OS failed to boot.
the dialogue displayed on the screen is is similar like this
boot failed:failed to start network manager wait online service.
i reinstall the os
and i type a command āsudo systemctl disable networkmanageā
taken from internet browsing.
but os booting failed this time also.
the difference was this time there is no dialogue or nothing but a blank screen with a frozen cursor.
i reinstall the os third time now.
i still did not update. iam afraid it will break my system again but i need to update the system for later drives of NVIDIA GPU card.
can you please help me to figure out this problem?
NB: i have another O.S called fedora in my system. but i install both OS in separate manual partitions
Did you know that the forum has a search function? 
Hello,
Just passed by to mention that this should be corrected, so new forum members will not get confused
āgenomeā (genetic material) should be Gnome.
Ok, the two mentioned services are not the same, even tho ārelatedā. Also remember that all names are case sensitive. If you want to mask/disable a service you need to use it as is.
systemctl mask NetworkManager-wait-online
can be done with no issue, but NetworkManager should not be stopped/masked/disabled unless you replaced that service with connman or use a different way to connect to internet automatically.
This solution doesnāt seem to work in my case.
It was not marked as solved. Try masking/disabling NetworkManager-wait-online service as bogdan suggested and reboot.