Not displaying correct windows in Window Buttons when using multiple Window Buttons applets on multimonitor

[Brendon Rapp]

I've been experiencing this one for a while.

I have three monitors, each with its own Panel on the bottom of the screen, and each panel has a Window Buttons applet.

On initial boot, the applets do *not* show the buttons for windows on that monitor.

What I have to do on each boot is:
  1. Open Panel Preferences
  2. Open the config for each Window Buttons applet
  3. Check "Show Windows from All Monitors" (which immediately populates the applet with buttons for ALL windows)
  4. Uncheck the very same box (which removes windows from other monitors, keeping only the windows for its own monitor)

After doing this, the Window Buttons applet on all monitors will behave as expected - adding and removing buttons for windows as they enter and leave that screen.

But until I do this little "toggle" trick to "wake" up the applet, they all simply Know Nothing, Jon Snow, and just stay blank.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[minphr (lp723h)]

I have a very similar problem for a few months now.

The way it is being fixed is exactly the same as Brendon Rapp reported in Bug Description.

There are a few differences:

- I have a laptop with one additional lcd monitor connected

- the applet on laptop's display is always fine - it is the panel of the additional display that's affected. But instead of not showing any buttons it displays a copy of those on the laptop's display applet

- it happens once in a few times

Since both screens show the same log in screen after boot, I guess it may be caused by the system not having switched to multi-monitor setup fast enough after logging in, so the applet checked for it before the system switched the mode of the additional monitor from a copy to a separate screen. I assume the applet defaulted to laptop's built-in display (I'm guessing) as a fallback from (at that time detected as) erroneous configuration

[Les Cunningham (les-cunningham)]

I have been having the same problem as minphr, except that I have a desktop computer with two monitors. The problem only occurs sometimes on the second monitor (which shows up as monitor 1 in Settings Manager - Display). I have only noticed this problem since installing Xubuntu 14.10 beta 2. Hardware is AMD (Richland) A8-6600K APU and Asus A88XM-PLUS motherboard, using the integrated Radeon graphics. The main monitor is connected to the DVI output and the second (smaller) monitor to the VGA output.

[zub (zub-linux)]

I did some searching in the upstream bug tracker and found these to be related:

https://bugzilla.xfce.org/show_bug.cgi?id=8806 - this is how I understand the original description of this bug

https://bugzilla.xfce.org/show_bug.cgi?id=9995 and https://bugzilla.xfce.org/show_bug.cgi?id=10725 - this so me seems like the comments #2 and #3. I'm alo experiencing this. The last Xfce bug report (10725) contains detailed info on why and how is the bug there.

[Gert Steyn (gert314)]

Having the same issue on xubuntu 16.04

[Sean Davis (bluesabre)]

Reportedly fixed upstream.