Valve has changed the way players in the Netherlands interact with loot boxes, possibly in a method to appease complaints by the Netherlands Gaming Authority earlier this year that found Dota 2 and Counter-Strike: Global Offensive in violation of its Betting and Gaming Act, according to GamaSutra.
A user on Reddit noticed the new system in Dota 2 and that it shows players exactly what in-game gear is held within their loot box purchase. Dutch players are still unable to use the Steam Marketplace, despite this change.
Source: IGN.com Players in the Netherlands Can Now See Loot Box Contents for Dota 2 Before Purchasing