There seems to be some confusion around here as to what exactly is being requested. It sounds to me like what paolov wants is to get rid of the global menu and just have the menus in the applications.

A change was made recently (plasma 5.13?) to get rid of the setting in System Settings and automatically set that up based on the presence of the Global Menu widget or the menu icon in the application's decoration.

If all you want is to have the standard menu bar in the application window, underneath the window title, the appropriate procedure is to simply remove the Global Menu widget from the panel. Then the menus should return to the applications (some applications may need to be closed and reopened for the change to take effect).

However, if having the menus in the panel is desired (or as a button in the window decoration) and the problem is that some (primarily gtk) applications still show it in the application, I'll refer you to https://blog.broulik.de/2018/03/gtk-global-menu/ which discusses the work that went into 5.13 around this.

I lost my nerves trying to set a global menu. In one neon linux it works in the other not. Everything is the same, everything you write but does not work in the other, the other neon is upgrade neon + xenial to neon + bionic. If I open another user I get a menu in Korean. I investigated and found that the upgrade also puts up a special neon module for the Koren version of the Neon. I uninstalled this module and the global menu is working in that user1, but my primary user does not work and can get it on my head.

airdrik wrote:There seems to be some confusion around here as to what exactly is being requested. It sounds to me like what paolov wants is to get rid of the global menu and just have the menus in the applications.
If all you want is to have the standard menu bar in the application window, underneath the window title, the appropriate procedure is to simply remove the Global Menu widget from the panel. Then the menus should return to the applications (some applications may need to be closed and reopened for the change to take effect).

Mmmmm... I've tryed it but without good result.
Now I resolved by modyfing the param "MenuBar = disabled" in "enabled" in al rc-files in the .config dir (I believe it can also work by removing the param).

@paolov,
That parameter I had and now it does not exist, the global menu works but not for all programs, it worked for Dolphin now not. It is unstable

edit.
Today I've tried Kubuntu with ppa Plasma 5.12.6 and ppa Frameworks 5.50. Only in Kubuntu 18.04 everything works without any additional installations, the global menu or the menu icon in the program decoration works ok.

Three things are required to get your menus back under the title bar.

1. cd into your .config folder and execute : find ./ -type f -exec sed -i 's/MenuBar=Disabled/MenuBar=Enabled/g' {} \;
2. In KDE settings > Window management > Menu tab > remove burger applications menu from title bar in both active and inactive windows
3. In KDE settings > Startup > Services > disable the menu daemon

Plus if you want your top menus in kate, hit ctrl+m twice.

enjoy.