Without unity-menubar.patch, aka. an official binary build of firefox wouldn't export its traditional menu to global menu plasmoid, nor the unity menu addon.
The applied patch works fine on its purpose: to export the menu to a global retriever, whether the DE is.
However, it fails to stay the browser consist when Mozilla introduced native client-side decoration (CSD) support on KDE.
When we don't use global menu plasmoid but disable titlebar (enable CSD), the window stays slim, and the tab bar stay tightly on top of the window left to the window control icons, but when we add the global menu plasmoid, the window gives a blank area where there is the window control icons on top right, then the opened tab bar. IMHO, it should stay on top like there is no the menu holder plasmoid.
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ProblemType: Bug
AddonCompatCheckDisabled: False
ApportVersion: 2.20.10-0ubuntu27
Architecture: amd64
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/controlC0: kubuntu 4436 F.... pulseaudio
BuildID: 20190410124846
CasperVersion: 1.405
Channel: Unavailable
CurrentDesktop: KDE
DistroRelease: Ubuntu 19.04
Extensions: extensions.sqlite corrupt or missing
ForcedLayersAccel: False
IfupdownConfig:
# interfaces(5) file used by ifup(8) and ifdown(8)
auto lo
iface lo inet loopback
IncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite)
IpRoute:
default via 10.0.2.2 dev enp0s2 proto dhcp metric 100
10.0.2.0/24 dev enp0s2 proto kernel scope link src 10.0.2.15 metric 100
169.254.0.0/16 dev enp0s2 scope link metric 1000
LiveMediaBuild: Kubuntu 19.04 "Disco Dingo" - Release amd64 (20190416)
Locales: extensions.sqlite corrupt or missing
Package: firefox 66.0.3+build1-0ubuntu1
PackageArchitecture: amd64
PrefSources: prefs.js
ProcVersionSignature: Ubuntu 5.0.0-13.14-generic 5.0.6
Profiles: Profile0 (Default) - LastVersion=66.0.3/20190410124846
RunningIncompatibleAddons: False
Tags: disco
Themes: extensions.sqlite corrupt or missing
Uname: Linux 5.0.0-13-generic x86_64
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups: adm cdrom dip lpadmin plugdev sambashare sudo
_MarkForUpload: True
dmi.bios.date: 04/01/2014
dmi.bios.vendor: SeaBIOS
dmi.bios.version: 1.12.0-20181126_142135-anatol
dmi.chassis.type: 1
dmi.chassis.vendor: QEMU
dmi.chassis.version: pc-q35-4.0
dmi.modalias: dmi:bvnSeaBIOS:bvr1.12.0-20181126_142135-anatol:bd04/01/2014:svnQEMU:pnStandardPC(Q35+ICH9,2009):pvrpc-q35-4.0:cvnQEMU:ct1:cvrpc-q35-4.0:
dmi.product.name: Standard PC (Q35 + ICH9, 2009)
dmi.product.version: pc-q35-4.0
dmi.sys.vendor: QEMU
Thanks for the report.
Can you please run the following command in a terminal to attach additional information to the bug report?
apport-collect 1824507