Choose whether the overall colors should switch with the system appearance or rather always stay light or dark.
Have text differences (Added, Deleted, Changed) shown in different colors or in a single color.
Font
Choose font and size to use for text.
Set the line height a bit more dense, normal or more relaxed.
Set the number of spaces to inset for a tab character.
View Settings
Wrap Long Lines: choose whether long lines should wrap to keep all text visible on screen, or stay on a line, showing scroll bars instead.
Show Line Numbers: toggle the line number column.
Show Invisible Characters: when enabled, Kaleidoscope shows so-called invisible characters (tab, newline, …) in areas with differences. Invisible characters outside changed areas will never be shown.
Processing
Ignore Differences in Whitespace: depending on your content, differences in whitespace (tabs or newlines) may not be relevant to make up a "change". Use this setting to set the ignore behavior to suit your needs.
Normalize JSON: As the order of keys in a JSON object does not have significance and is thus often "random", it is very hard to compare JSON, in particular when it has been written by a generator. Normalization will impose a default order, enabling a visual comparison between two bits of JSON content. However, for some use cases this may not be desirable.