Hi Alessandro.

El Fri, 8 Feb 2019 21:53:44 +0100
Alessandro Selli <alessandroselli@???> escribió:

>     This afternoon I happened to be surprised I could not use my
> laptop's GUI because the screen was unresponsive to both keyboard and
> mouse.  The laptop was not frozen though, a clock in the DM display was
> running.
>
>   Logging-in from another PC [...]

In common situations there is no need to login from another PC.
You can press Ctrl-Alt-F1 (handled by the kernel, not by the X system)
to get a text console (Alt-F7 to go back to the graphics).

This is valid for most standard configurations.

-- 
   Gonzalo Pérez de Olaguer Córdoba       salo@???
  -=- buscando empleo desde 1988 -=-       www.gpoc.es 

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