This is a really minor display issue, but I notice it often enough to figure it's worth mentioning. The chest graphic accompanying the "Multiplayer" button in the upper left-hand corner of the main campaign screen seems intended to show what kind of chest you are eligible for on your next win. When I haven't done any fights yet, it shows gold. If, when I log into the game, I have already won one fight (and so am only eligible for a regular chest for win #2), it shows a regular chest. BUT, if I log in not having done any fights, win one (getting the gold chest), and then go to campaign mode, it still shows a gold chest even though I'm only eligible for a regular one on my next win. Logging out and back in changes it to a regular chest, which makes me think that it not updating dynamically if you stay logged in is not the intended behavior.
This bug is a real veteran. It's been 1 year and 8 months since it was first spotted. https://forums.cardhunter.com/threads/mp-chest-icon.1469/ I guess it's still low priority?