Prevent tiles with chests from falling.

src/monster.c

@@ -586,7 +586,7 @@ monster_update(Monster *m, UpdateData *data)
 
 	sprite_update(m->sprite, data);
 
-	if (m->sprite->state == SPRITE_STATE_FALLING && m->sprite->dim.width < 4) {
+	if (m->sprite->hidden == SPRITE_STATE_FALLING && m->sprite->hidden) {
 		m->stats.hp = 0;
 		player_monster_kill_check(data->player, m);
 		return;

src/player.c

@@ -300,7 +300,8 @@ move(Player *player, RoomMatrix *matrix, Vector2d direction)
 		    lastPos.y < 10 &&
 		    lastSpace->decoration == NULL &&
 		    lastSpace->trap == NULL &&
-		    lastSpace->objects == NULL
+		    lastSpace->objects == NULL &&
+		    lastSpace->items == NULL
 		    )
 			map_trigger_tile_fall(lastSpace->tile);
 	}

src/sprite.c

@@ -136,8 +136,10 @@ sprite_update(Sprite *s, UpdateData *data)
 					s->dim.height /2
 				};
 			}
-			if (s->dim.width < 4)
+			if (s->dim.width < 4) {
 				s->hidden = true;
+				s->state = SPRITE_STATE_DEFAULT;
+			}
 		}
 	}