It appears the game has colour coded backgrounds for everything Legendary related (chests, materials, outfits) according to rarity, which is consistent across the whole game: Common - brown Uncommon - green Rare - blue Epic - purple Legendary - orange With one exception. Opening Battered Chests (listed as common), which shows an awkward light blue background.
This issue persists into 2.3.0. The correct background is shown in the list of chests but changes to the light blue one when opening Battered Chests or Bandit's Chests.
