General
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Format: Select your desired default composition format here. New compositions will be created in the selected format.
Background: Define your default background for new compositions here.
Preview options: If you need a frames-per-second display in the preview, you can activate it here.
Library
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Graphics: Here you set the repository paths for the libraryLibrary. The library Library looks for files in the specified directories and these files will then be represented in the libraryLibrary. The home folder of each OS X macOS user has standard locations in which media files are stored, so these are the default paths.