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The mvc.themes property specifies the name for the theme which will be displayed in the Runtime theme selector. The other two properties specify which StringTemplate index file should be used and which StringTemplate function should be called to render the index page (see "Creating the index file" above). The path to the index file is relative to either the JAR or the
folder. When a filename is specified which is located in and that is already loaded from a JAR, the file from will be used and the file from the JAR will be overridden. More information about overriding existing themes can be found on Extending themes.