Installation & Boot on notebok with closed lid and connected monitor

[luckas]

Sorry for my English. When I try install or boot LM20 on notebook with closed lid and connected monitor I can't anything see on the screen - image flickers and twitches. And the reason, I believe, is this:
xrandr --listactivemonitors
Monitors: 2
0: +*DP-1 1920/518x1200/324+0+0 DP-1
1: +*DP-1 1920/518x1200/324+1920+0 DP-1
If I run:
xrandr --output DP-1-0 --off
or I open and then close lid everything is going back to normal:
Monitors: 1
0: +*DP-1 1920/518x1200/324+0+0 DP-1

DP-1 external d-sub monitor.
I tested on different notebooks (BIOS or UEFI, one or two videocards) and taked same effect.This is only in LM20, in LM19 all ok!

[myface68]

Your laptop monitor is set as primary. In display set to mirror.

[luckas]

laptop monitor is set as primary.

You're wrong, it's not:
$ xrandr -q
Screen 0: minimum 320 x 200, current 3840 x 1200, maximum 16384 x 16384
eDP-1 connected (normal left inverted right x axis y axis)
1920x1080 60.01 + 60.01 59.97 59.96 59.93 40.00
....
HDMI-1 disconnected (normal left inverted right x axis y axis)
DP-1 connected primary 1920x1200+0+0 (normal left inverted right x axis y axis) 518mm x 324mm
1920x1200 59.95*+
.....
HDMI-2 disconnected (normal left inverted right x axis y axis)
This is before 'xrandr --output DP-1-0 --off'