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First of all, I apologize for my English, I am using a translator, I hope you can understand me.
Well, I've been using Arch Linux for a long time and I haven't had too many complications, all the errors that came up I was able to solve, but this one is different and I can't think of anything to solve it.
I would not know how to indicate to simulate the error because I do not understand what exactly happened. I was installing Web-Greeter for LightDM, I only installed it, but I did not configure it, in the end I uninstalled it because I ended up discarding it and I kept having lightdm-webkit2-greeter installed and configured. Anyway, I turned off my laptop for later, but when I turn it back on I get a black screen.
I tried to access a TTY terminal, but it did not access, it was as if the system was constantly rebooting trying to start LightDM and every time I access the TTY it boots without being able to do anything, nor being able to see the LightDM configuration.
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Boot the multi-user.target (2nd link below) and check the lightdm.conf for the configured greeter, https://wiki.archlinux.org/title/LightDM#Greeter
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if I have udenstand right please see below the solution from Arch wiki:
It may happen that your system boots so fast that LightDM service is
started before your graphics drivers are properly loaded.
If this is your case, you will want to add the following
config to your lightdm.conf file:
sudo nano /etc/lightdm/lightdm.conf
[LightDM]
logind-check-graphical=true
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