Rhythmbox doesn't offer a menu anymore

[Sascha Biermanns]

Within the last two weeks, rhythmbox lost it's menu, so it's not possible to access the plugins, settings or anything else, except you know what the menu point was called - and press ALT, using the HUD to access the settings or whatever.

Using the system menu to change, where the menu should be (window or top panel) has no effect.

rhythmbox:
  Installiert: 3.3-1ubuntu6
  Installationskandidat: 3.3-1ubuntu6
  Versionstabelle:
 *** 3.3-1ubuntu6 500
        500 http://de.archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        100 /var/lib/dpkg/status

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: rhythmbox 3.3-1ubuntu6
ProcVersionSignature: Ubuntu 4.4.0-15.31-generic 4.4.6
Uname: Linux 4.4.0-15-generic x86_64
ApportVersion: 2.20-0ubuntu3
Architecture: amd64
CurrentDesktop: Unity
Date: Tue Mar 29 10:02:29 2016
ExecutablePath: /usr/bin/rhythmbox
InstallationDate: Installed on 2016-03-16 (12 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Alpha amd64 (20160307)
ProcEnviron:
 PATH=(custom, user)
 SHELL=/bin/bash
 LANG=de_DE.UTF-8
 LANGUAGE=de_DE
 XDG_RUNTIME_DIR=<set>
SourcePackage: rhythmbox
UpgradeStatus: No upgrade log present (probably fresh install)