When syntax coloring turned on in the source window, comments will be colored red, commands will be colored blue, and the symbols $, {, and } will be colored dark green. A few users may wish to change these colors. Each color is determined by setting its red, green, and blue components; these components are real numbers between 0.0 and 1.0. Suppose we wish to change the color of $, {, and } to bright green, a color with components (r, g, b) = (0.0, 1.0, 0.0). To do so, open the Terminal window and type the following commands

defaults write TeXShop markerred 0.0
defaults write TeXShop markergreen 1.0
defaults write TeXShop markerblue 0.0

The corresponding preference items for comments are commentred, commentgreen, commentblue; the items for commands are commandred, commandgreen, commandblue.

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Syntax Colors