Currently, if an add-on package defines new scopes, it’s not likely to work with existing themes. For example, many color schemes don’t work with markdown documents because they don’t definitions for the necessary scopes. Some plug-ins go to extreme lengths to work around this: the SublimeLinter plugin reads the user settings to determing which theme you’re using, runs a regex search on the .tmtheme file to figure out if it has styles for the necessary scopes, and if not generates a copy of the theme with the new scopes added, and updates the user settings to use the new theme.

It’s even worse if a package wants to use colors from an existing scheme in new ways - it would be great if a markdown theme could just say, set this new scope to use the same style as that other already existing scope.

Is there any chance of a future version of ST allowing programmatic access to color schemes?