The Appearance Options dialog sets preferences for the overall appearance of Liquib.  The default Liquib interface, with colors on a dark background, can be difficult to see on some monitors, or even hard on the eyes.  (And some people just don't like it!)  In such cases, the Interface Style can be switched to Standard Windows, which provides a more conventional appearance.  A Background Color can be chosen for the screen area where images are displayed.  The size of text, buttons and other controls can be adjusted by switching the Interface Scale from the default Normal to Tiny, Large or Jumbo.
Appearance Options - Liquib Original Interface Style Appearance Options - Standard Windows Interface Style