Comment # 7 on bug 1133696 from Maurizio Galli

(In reply to Carlos Robinson from comment #6)
> Elesar:~ # rpm -qi openSUSE-release
> Name        : openSUSE-release
> Version     : 15.1
> Release     : lp151.292.2
> Architecture: x86_64
> Install Date: Tue Apr 30 13:54:27 2019
> 
> 
> Which is surely not the build number, as I did a zypper dup today, May 3.
> 
> 
> I have not touched appmenu, global-menu. If they are programs, they are not
> installed.
> 
> Elesar:~ # appmenu
> If 'appmenu' is not a typo you can use command-not-found to lookup the
> package that contains it, like this:
>     cnf appmenu
> Elesar:~ # global-menu
> If 'global-menu' is not a typo you can use command-not-found to lookup the
> package that contains it, like this:
>     cnf global-menu
> Elesar:~ # 
> 
> If they are files, please tell path and I'll verify against rpm database if
> they have changed.

They are panel plugins known to mess with menubars but not part of any default
configuration. 

> 
> This is a fresh install, made using
> openSUSE-Leap-15.1-DVD-x86_64-Build450.2-Media.iso, then zypper duped
> several times. I deleted ~/.config/libreoffice days ago and did no effect.
> I'll try now again. [...]  No change.
> 
> I use XFCE only.
> 
> No difference if lo started from command line.
> 
> I can try on a new user.


Libreoffice does have an hidden option to toggle on/off the menubar. And I
wonder if it's the cause. 

Try this:

1. rightclick on one of the buttons on the toolbar to get a context menu.
2. Select: Customize Toolbar and search "Menubar". 
3. add the "Menubar" button to the toolbar. 
4  use the button you just added to toggle menubar on and off

screenshot: https://imgur.com/a/QIBUNl0