VirtualBox GUI infinite loop changing window layout - GUI unusable

[marco.m]

The GUI keeps flapping, with a frequency circa 1 sec, between two different layout, as you can see in the two screenshots attached. It looks like the layout/resize logic of the GUI is wrongly wired and in certain cases it can enter an infinite loop.

Worst problem is not the flapping, is the fact that the whole GUI is unresponsive, it is even impossible to reach the menu and to quit. Only way to quit is to "force quit" from Activity Monitor on macOS.

[marco.m]

This happened when I added a second hard disk to the VM using the command-line. Before the GUI was working fine.

I did the following changes:

1. in the GUI, renamed the Storage Controller Name from "IDE Controller" to "IDEController", removing the space. This to work around the following bug:

VBoxManage storageattach beaglebone_default_1548278259826_34227 --storagectl "IDE Controller" ... VBoxManage: Error: Invalid parameter 'Controller'

2. Attached a raw disk to the selected VM

VBoxManage storageattach beaglebone_default_1548278259826_34227 --storagectl IDEController ...

3. Started the GUI app to have a look -> the window layout flip/flap started.

In case this can help, I created the VM configuration with Vagrant.

[marco.m]

2019-02-06

I just checked with latest VBox 6.0.4 and is still flaps as above. Still only way to quit is to force quit from the Activity Monitor. Activity Monitor shows CPU constant at 100% for VBox with 0 VMs running :-(