System fails to start using two kernels, install secondary DE and how to switch desktop environment?

Two 5.x kernels (installed within Manjaro kernel manager) fails to boot into desktop environment (default XFCE) for me (i do not rember exact message, it just stuck on “Manjaro Failed to start Light Display Manager.” and “journalctl --list-boots” shows only current boot so i do not know exact message), so i was thinking if i can do some command inside console (to which i can switch using Ctrl+Alt+F5 (or Ctrl+F5?)) so i start different desktop environment which i would install Install Desktop Environments - Manjaro

Or it is not worth the effort? I am also asking because this crap computer system is freezing like every day no matter which of the working kernel i am using (5.15, 5.10 + xfce), maybe DE/GPU can be related.

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So it seems time to test your hardware.

Maybe use a live manjaro for one day, and see if it freezes also.

Here in this forum are a lot of threads you could look for, in which is described how to proceed, when DE does not start.

NO SOLUTION IN THIS POST

test your hardware.

How you would do it, which commands, you know any tutorial?

live manjaro

does not seem like an option, i need to run numerous apps that has data on ZFS filesystem + system configurations + i do not believe this will lead to a fix. I can spend time trying to figure out how tu run ZFS on live, how copy/transfer apps configuration. But what if system not crash, then there is thousands of differences between live and my current system…

when DE does not start

i doubt it is just a DE, i see that numerous services fails, like lightdm, wireguard, network related and other. under 5.15 and 5.10 works OK though. I can supply information, it is not the problem, problem is if there is anyone who can suggest which command/s is needed to supply needed information and is able to understand that information and find the cause without spending hours and hours on this like one month old issue. A bit frustrated about numerous unsolved issues, so sorry for my pessimistic post. If You want to complain about my attitude, please do it via PM to keep this on topic.