Menubar missing in Libreoffice 5.2 on Debian

I’m pretty sure this is a GTK3 thing. If I uninstall the package

, I get the menubar back. I’m using Awesome window manager on a fairly bare-bones Debian setup. I know I have to change some GTK3 setting or Gnome setting or something in order to get the menubar to show up, but I can’t figure out what that is.