Topic on Store talk:Steam
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> AFAIK the functionality never really left.
It absolutely did as I was the one that wrote and later updated the PCGW section after Valve had removed the built-in option. Data _was_ downloaded, but despite the manifest being specified, the Steam client would always download the latest manifest so it was functionally useless.
It's possible they fixed that at one point or another though -- I'll verify it as well today.