[xubuntu-users] How to get the right information about a "crash"

[Willem Hobers]

Hello all,

I hope this is the right channel for my question; if not please advice 
me where to go next.
I am pretty much a noob; also: English is not my native language.

Running: xubuntu 16.04, updated.
Linux LPT001 4.8.0-58-generic #63~16.04.1-Ubuntu SMP Mon Jun 26 17:59:49 
UTC 2017 i686 i686 i686 GNU/Linux

Hardware:
LENOVO_MT_80UD_BU_idea_FM_Lenovo
Lenovo ideapad 1
Intel(R) Core(TM) i3-6100U CPU @ 2.30G

Every now and then, quite unpredictably, I am thrown out of a session, 
the screen turns black and I am then presented with the login screen. I 
log in again, and am presented with a working session again, but no 
applications are running anymore, and I get a dialogue which tells me 
some system error occurred and would I like to report it. I always do. 
The details of the dialogue tells me the error is in Xorg.

My questions:

- I assume that my error is sent to someone, somewhere. Where can I go 
to find the error that is being sent; is that somewhere online? Launchpad?
- where, on my machine, can I find the error message if I would like to 
examine it?
- do I need to "warn" some one at Xubuntu, if so: how?

Thanks!
I will gladly provide more information,.
Willem