Bug 350707 - Black screen when undocking/docking laptop with two external monitors
Summary: Black screen when undocking/docking laptop with two external monitors
Status: RESOLVED UPSTREAM
Alias: None
Product: plasmashell
Classification: Plasma
Component: general (show other bugs)
Version: 5.3.2
Platform: Fedora RPMs Linux
: NOR normal
Target Milestone: 1.0
Assignee: David Edmundson
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2015-07-28 12:28 UTC by Jaroslav Reznik
Modified: 2015-10-05 14:43 UTC (History)
6 users (show)

See Also:
Latest Commit:
Version Fixed In:

Attachments
Add an attachment

Note You need to log in before you can comment on or make changes to this bug.
Description Jaroslav Reznik 2015-07-28 12:28:07 UTC 
When undocking and then docking again (one internal laptop screen and two external monitors), plasma shell is not shown on internal LCD. It's just black screen, nothing is clickable.

Log excerpt from console:
requesting unexisting screen 2
requesting unexisting screen 1
(repeats many times)

kscreen-konsole bug output http://fpaste.org/248887/80862971/

Reproducible: Always

Steps to Reproduce:
1. use Plasma Desktop with two external monitors attached to docking station
2. undock laptop, Plasma works as expected - everything is moved to the internal LCD
3. dock it again

Actual Results:  
No Plasma Desktop on the internal LCD, just blank screen

Expected Results:  
Plasma Desktop usable on the internal LCD
Comment 1 Tom 2015-07-28 13:41:14 UTC 
Yes this bug is confirmed on Arch Linux plasma 5.3.2. and qt5.5.0.
When that happen you really can't do much. In my case I used one external monitor.
Comment 2 Jaroslav Reznik 2015-07-28 13:46:59 UTC 
(In reply to Tom from comment #1)
> Yes this bug is confirmed on Arch Linux plasma 5.3.2. and qt5.5.0.
> When that happen you really can't do much. In my case I used one external
> monitor.

You can restart Plasma - easiest way is Alt+F2 and "kquitapp5 plasmashell && plasmashell".
Comment 3 Sandro 2015-08-08 01:23:41 UTC 
Firstly... this affects me.  I commented on another bug but this one, now that I found it, is exactly what I'm seeing.  I also get it when there is just one external monitor.  When using another DM (tried XFCE and Gnome3), this problem does not exist.

(In reply to Jaroslav Reznik from comment #2)
> (In reply to Tom from comment #1)
> > Yes this bug is confirmed on Arch Linux plasma 5.3.2. and qt5.5.0.
> > When that happen you really can't do much. In my case I used one external
> > monitor.
> 
> You can restart Plasma - easiest way is Alt+F2 and "kquitapp5 plasmashell &&
> plasmashell".

...and anything unsaved is *poof*

For me, I'd consider a workaround something that brings back the session.  Anything else is no different than a reboot to me.
Comment 4 Alvin 2015-10-01 13:13:41 UTC 
Confirmed on Kubuntu 15.10 (beta2) with plasma 5.4.1 on a normal dual-monitor setup. 1 monitor is blank, but can be used to move windows to. Restarting plasmashell activates it.
Comment 5 Christoph Cullmann 2015-10-05 14:43:15 UTC 
Thats one of the many variants of

https://bugreports.qt.io/browse/QTBUG-42985

And no, not fixed, not even with all patches in that bug.
Please report more info there, to give them a better chance to fix it and raise
awareness, the kde bugtracker doesn't help for that.