The template assumes the group id is "mediawiki-skin-X". But for the skins at GitHub the group id is "mwgithubskin-X". It should be configurable.
Topic on Template talk:Skin/Flow
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The template assumes the group id is "mediawiki-skin-X". But for the skins at GitHub the group id is "mwgithubskin-X". It should be configurable.