VirtualBox top menu missing (not showing)? How to get it back
VirtualBox top menu missing (not showing)? This tutorial will show you in a few steps how to get it back.
The top menu I'm talking about consists of File, Machine, View, Input, Devices, and Help.
Solution
1. Make sure your VM (virtual machine) is running (e.g., Linux Mint, Ubuntu, Microsoft Windows, etc.).
2. Press the right [CTRL] + [Home] key (ctrl key on the right side of your keyboard).

3. Go to View > Menu Bar and then click on Show Menu Bar.

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