(1) Ensure that the terminal widgets doesn't use keyboard events.
Advantage: keyboard navigation and selection doesn't interfere
with the display.
Drawback: Contents of the terminal can no longer be copied.
This will be addressed in a later update.
(2) Thanks to Manolo for his addition of the "GUI scaling" button.
Although GUI scaling can be useful, it can also be annoying while
testing shortcuts.
(3) Changed all light buttons to check buttons.
