We guys don't release anything; It is 1 person who releases the Windows X package.
Furthermore, all the skins in it are created by other people. And those people will release their skins seperate (somewhere, you need to search) if they still are updating the skins. If the skins aren't updated for newer Messenger versions, then the creator of the Windows X Package updates them himself and thus no seperate release for that particular skin...
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