Windows not shown in switcher until its configuration is changed

[arty]

I have a unity desktop in Ubuntu 16.04 with 1 workspace. When I press Alt+Tab, I do not see in the switcher windows of some apps. Franz (http://meetfranz.com/) is one example. Also the triangle beside its icon in launcher is only contoured, and not filled like for other apps (see screenshot).

Curiously enough, when I launch CompizConfig, open Ubuntu Unity Plugin settings, and in the Switcher tab switch some checkbox on and off again, i.e. "Switcher strictly changes between applications", then the missing windows appear in the switcher. The triangle remains only contoured though.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: unity 7.4.0+16.04.20160526.1-0ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13
Uname: Linux 4.4.0-31-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_modeset nvidia
.proc.driver.nvidia.gpus.0000.01.00.0: Error: [Errno 21] Ist ein Verzeichnis: '/proc/driver/nvidia/gpus/0000:01:00.0'
.proc.driver.nvidia.registry: Binary: ""
.proc.driver.nvidia.version:
 NVRM version: NVIDIA UNIX x86_64 Kernel Module 361.42 Tue Mar 22 18:10:58 PDT 2016
 GCC version: gcc version 5.4.0 20160609 (Ubuntu 5.4.0-6ubuntu1~16.04.1)
.tmp.unity_support_test.0:

ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
Date: Fri Jul 15 13:44:32 2016
DistUpgraded: 2016-04-22 12:28:10,404 DEBUG icon theme changed, re-reading
DistroCodename: xenial
DistroVariant: ubuntu
GraphicsCard:
 Intel Corporation 4th Gen Core Processor Integrated Graphics Controller [8086:0416] (rev 06) (prog-if 00 [VGA controller])
   Subsystem: Lenovo 4th Gen Core Processor Integrated Graphics Controller [17aa:221e]
 NVIDIA Corporation GK106GLM [Quadro K2100M] [10de:11fc] (rev a1) (prog-if 00 [VGA controller])
   Subsystem: Lenovo GK106GLM [Quadro K2100M] [17aa:221e]
InstallationDate: Installed on 2016-03-01 (135 days ago)
InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021)
MachineType: LENOVO 20BG001SGE
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-31-generic.efi.signed root=UUID=3045dd51-1659-4fdc-9d9a-fa5c0e1a39c9 ro quiet splash vt.handoff=7
SourcePackage: unity
UpgradeStatus: Upgraded to xenial on 2016-04-22 (84 days ago)
dmi.bios.date: 01/26/2016
dmi.bios.vendor: LENOVO
dmi.bios.version: GNET78WW (2.26 )
dmi.board.asset.tag: Not Available
dmi.board.name: 20BG001SGE
dmi.board.vendor: LENOVO
dmi.board.version: 0B98401 Pro
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvrGNET78WW(2.26):bd01/26/2016:svnLENOVO:pn20BG001SGE:pvrThinkPadW540:rvnLENOVO:rn20BG001SGE:rvr0B98401Pro:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 20BG001SGE
dmi.product.version: ThinkPad W540
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.12.2+16.04.20160526-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.67-1ubuntu0.16.04.1
version.libgl1-mesa-dri: libgl1-mesa-dri 11.2.0-1ubuntu2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 11.2.0-1ubuntu2
version.nvidia-graphics-drivers: nvidia-graphics-drivers-* N/A
version.xserver-xorg-core: xserver-xorg-core 2:1.18.3-1ubuntu2.2
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.10.1-1ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:7.7.0-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20160325-1ubuntu1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.12-1build2
xserver.bootTime: Fri Jul 15 09:35:52 2016
xserver.configfile: /etc/X11/xorg.conf
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.version: 2:1.18.3-1ubuntu2.2