So you've just looted after finishing a battle and are now looking at the intro page for the next battle. We know you can drag back down to your inventory and poke at your loot, including swapping equipment. Blue Manchu already intends to re-code that one of these days: you're supposed to use the "Modify Party" button to see the inventory again, not drag the screen. Well, meanwhile, there are weird issues with the chest. After dragging the screen, if you drop loot into the chest then it stays there. You can't get it out. (Fortunately, you don't lose the loot permanently.) But then hit the "Modify Party" button while you have loot stuck in the chest, and then hit the "Try Again" button. Now the "Modify Party" button ceases to function. You have to return to the map to get the functionality back. There are also minor issues including the loot-stuck-in-the-chest appearing to vanish (but this is only visual: you get the item back after you leave and return), and some extra clicking required to move items into the chest once more. Mostly, yeah, it's weird and comes from the player abusing the game, but I figured it's more encouragement to re-code the section.
Hold the phone: the loss of the "Modify Party" button has nothing to do with this fiddling. All you have to do is go back and forth between the two screens. The button shortly will cease to function and you'll have to return to the map and go back in if you wish to change equipment. Has this been reported already?