If the colors and subsequently brushes and the like would be a library saved with each xar file it would make each single xar file enormous.
My personal way is to create a xar file(s) with my colors,brushes and even OCC shapes and save these as some sort of library file.
Use the following option in the Utilities>Options>Backups: "Backup open files on program close and restore on program start"
Now I can get the colors,brushes,... to be used (semi)globally by selecting them in their designated galleries.
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