Introduction[edit]

This procedure is experimental and has not been widely tested.

This procedure is an alternative to using VirtualBox Guest Additions for a higher screen resolution. See also: Security Considerations.

Before attempting this procedure it is recommended to have a recent backup in case problems are encountered. However, it should be possible to undo these changes.

Higher Screen Resolution without VirtualBox Guest Additions[edit]

To achieve a higher screen resolution without installing VirtualBox guest additions, complete the following steps.

1. Create a relevant configuration file.

For example, create a file called /etc/X11/xorg.conf.d/00-virtualbox-monitor.conf.

Create the directory if it does not already exist.

sudo mkdir -p /etc/X11/xorg.conf.d

sudo mkdir -p /etc/X11/xorg.conf.d

2. Open the configuration file in an editor with root rights.

sudoedit /etc/X11/xorg.conf.d/00-virtualbox-monitor.conf

sudoedit /etc/X11/xorg.conf.d/00-virtualbox-monitor.conf

3. Add the following contents.

Section "Device"
  Identifier "VirtualBox-Device"
  Option "Monitor-default" "VirtualBox-Monitor"
EndSection

Section "Monitor"
  Identifier "VirtualBox-Monitor"
  VendorName "VirtualBox"
  ModelName "VirtualBox"
  HorizSync 1.0 - 1000.0
  VertRefresh 1.0 - 1000.0
  Option "MinClock" "1.0"
  Option "MaxClock" "10000.0"
  Option "Primary" "True"
  Option "PreferredMode" "1600x1200"
EndSection

Section "Screen"
  Identifier "MyScreen"
  Device "VirtualBox-Device"
  Monitor "VirtualBox-Monitor"
EndSection

Section "Device"
  Identifier "VirtualBox-Device"
  Option "Monitor-default" "VirtualBox-Monitor"
EndSection

Section "Monitor"
  Identifier "VirtualBox-Monitor"
  VendorName "VirtualBox"
  ModelName "VirtualBox"
  HorizSync 1.0 - 1000.0
  VertRefresh 1.0 - 1000.0
  Option "MinClock" "1.0"
  Option "MaxClock" "10000.0"
  Option "Primary" "True"
  Option "PreferredMode" "1600x1200"
EndSection

Section "Screen"
  Identifier "MyScreen"
  Device "VirtualBox-Device"
  Monitor "VirtualBox-Monitor"
EndSection

4. Run restart lightdm ^[1] or reboot.

Whonix ™ will now be set to 1600x1200 mode by default.

5. Optional: Change the default resolution mode.

If a default resolution mode other than 1600x1200 is preferred, then change the "PreferredMode" option in the "Monitor" section.

It is possible to dynamically switch modes from the command line with "xrandr --output default --mode [resolution value]". To view a list of available modes, run "xrandr".

6. Optional: Change the screen resolution using the KDE graphical user interface.

Start Menu → System Settings → Display and Monitor.

If the preferred screen resolution is not listed (e.g. 1440x900), try running this command on the host.

vboxmanage setextradata "VM Name" "CustomVideoMode1" "1440x900x32"

vboxmanage setextradata "VM Name" "CustomVideoMode1" "1440x900x32"

If the Start Menu button is not visible (because it is outside the screen), then start Konsole and manually start System Settings by running systemsettings.

Ubuntu[edit]

This procedure was recommended for an earlier version of Ubuntu (14.04). Functionality in later versions has not been confirmed (e.g. Ubuntu 20.04).

If Ubuntu has a screen resolution of 640x480, it may be possible to achieve 1024x768 by:

Running xdiagnose.
Changing any setting under Debug -- marking them all or unmarking "Enable automatic crash reporting" were previously reported to work.
Reboot.

Security Considerations[edit]

Follow these steps to minimize anonymity threats:

To prevent fingerprinting it is safest to not maximize the Tor Browser window. ^[2] ^[3]
To prevent accidentally maximizing a window, it is recommended to deactivate the following option: KDE → System Settings → Screen Edges → Uncheck: Maximize Windows by dragging them to the top of the screen.
It might also be safer to not use the same screen resolution as the host.

Troubleshooting[edit]

If this procedure does not work or you want to revert the changes, delete /etc/X11/xorg.conf.d/00-virtualbox-monitor.conf.

sudo rm /etc/X11/xorg.conf.d/00-virtualbox-monitor.conf

sudo rm /etc/X11/xorg.conf.d/00-virtualbox-monitor.conf

Next, run restart lightdm ^[1] or reboot.

Technical Information[edit]

EDID[edit]

An anonymous user stated:

The reason you can't just get higher resolutions using xrandr "--newmode" and "--addmode" without an xorg.conf file appears to be that VirtualBox is not providing EDID information to the default VESA driver. The driver therefore makes the conservative assumption that it can't drive the "monitor" with the high clock rates needed for larger display sizes. The above config file tells the driver that it can use an effectively infinite range of clock rates.

Also see: VirtualBox get-edid output.