How to Set Background Color of Editor in MPLab X?
Under the MPLAB X IDE the language specific options only apply to specific elements that are identified as forming part of the language. It's useful to apply different colors for things such as comments however if applied to a character for example the background only changes for elements not identified as being something else:



Instead to make global changes to the background it's best to use the "all languages" selection. The language specific settings tend to inherit their background colour from those default settings so by making a single change it will change the background color of all elements: