[Invalid] window borders in theme settings

[rok]

I've installed Linux Mint 19.1 in VBox. My host is Linux Mint 18.3.

When I set themes I plenty of options available for icons, controls and desktop, but not for window borders. I only have Mini-X, Mint-Y and Mint-Y dark available for window borders in the guest machine. None of which I like.

On the host machine I have about 16 different options, many of which I find in my /usr/share/themes directory.

I don't know where 'window borders' files would normally be to make the choices I really want available.

Any help would be appreciated.

[socratis]

This is not a VirtualBox question, marking the thread as [Invalid].

Just because an OS/program that runs in the context of VirtualBox has a problem, it doesn't make it a VirtualBox problem necessarily. You're having an issue that has nothing to do with VirtualBox, so my suggestion would be to treat it as such, as a native problem with the OS of the guest.

If you go into the "Themes", there's an option on the top to "Add/Remove". Enjoy/have fun...