[Client] "Item is not available on the following maps:" not showing Summoner's Rift

When checking the tooltip of an item in Item Sets, no items which are unavailable in Summoner's Rift indicate as such, though will indicate if they are unavailable on Crystal Scar/Twisted Treeline/Howling Abyss. It is isolated to just Summoner's Rift.

1. Load up client.
2. Go to Summoner Profile -> Item Sets
3. Search for an item which is not available in Summoner's Rift (ex. Moonflair Spellblade, Wooglet's Witchcap)
4. Scroll over item for the tooltip. At the bottom where it writes "This item is not available on the following maps:" they do not include Summoner's Rift.

Appears to occur with all items. Special note: Items which are only unavailable on Summoner's Rift still have "This item is not available on the following maps:" written out, but indicates no maps in which it is unavailable (ex. Wicked Hatchet), contrary to items available on all maps such as Void Staff which do not have that line at all.