I can observe the problem in a 19.10 VM in a kubuntu session. This is an Ubuntu-specific problem, upstream builds don't exhibit the issue (but they don't export menus either).
I can observe a similar issue with firefox using CSD in a 16.04 VM running a Unity session: menus are exported in the top panel, but the height of the title bar is twice what it should be, the top part being empty except for the window buttons (see attached screenshot).?field.comment=I can observe the problem in a 19.10 VM in a kubuntu session. This is an Ubuntu-specific problem, upstream builds don't exhibit the issue (but they don't export menus either). I can observe a similar issue with firefox using CSD in a 16.04 VM running a Unity session: menus are exported in the top panel, but the height of the title bar is twice what it should be, the top part being empty except for the window buttons (see attached screenshot). ** Attachment added: "VirtualBox_xenial amd64_18_12_2019_17_56_18.png" https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1853893/+attachment/5313666/+files/VirtualBox_xenial%20amd64_18_12_2019_17_56_18.png ** Changed in: firefox (Ubuntu) Status: New => Confirmed ** Changed in: firefox (Ubuntu) Importance: Undecided => Medium ** Summary changed: - Firefox maximized CSD using double space on Plasma with "global menu" widget + Firefox maximized CSD using double space on Plasma/Unity with "global menu" widget -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to firefox in Ubuntu. https://bugs.launchpad.net/bugs/1853893 Title: Firefox maximized CSD using double space on Plasma/Unity with "global menu" widget Status in firefox package in Ubuntu: Confirmed Bug description: Kubuntu 19.10 Firefox 70.0.1+build1-0ubuntu0.19.10.1 Using Firefox's CSD on KDE Plasma and using KDE's "global menu" widget in a panel, Firefox takes useless space for the "title bar". Screenshot here: https://pasteboard.co/IImEuh3.png By right clicking on the empty space in the "title bar", this space disappears for a few seconds giving this: https://pasteboard.co/IImFha5.png ProblemType: Bug DistroRelease: Ubuntu 19.10 Package: firefox 70.0.1+build1-0ubuntu0.19.10.1 ProcVersionSignature: Ubuntu 5.3.0-23.25-generic 5.3.7 Uname: Linux 5.3.0-23-generic x86_64 ApportVersion: 2.20.11-0ubuntu8.2 Architecture: amd64 BuildID: 20191031091608 CurrentDesktop: KDE Date: Mon Nov 25 19:57:39 2019 DefaultProfileExtensions: extensions.sqlite corrupt or missing DefaultProfileIncompatibleExtensions: Unavailable (corrupt or non-existant compatibility.ini or extensions.sqlite) DefaultProfileLocales: extensions.sqlite corrupt or missing DefaultProfilePrefErrors: Unexpected character ',' before close parenthesis @ /usr/lib/firefox/omni.ja:greprefs.js:930 DefaultProfileThemes: extensions.sqlite corrupt or missing ExecutablePath: /usr/lib/firefox/firefox InstallationDate: Installed on 2019-11-14 (11 days ago) InstallationMedia: Kubuntu 19.10 "Eoan Ermine" - Release amd64 (20191017) Profiles: Profile1 (Default) - LastVersion=None/None (Out of date) Profile0 - LastVersion=70.0.1/20191031091608 (In use) SourcePackage: firefox UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1853893/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp