I’ve noticed that some of the long paintings seem to have their “hitboxes” flipped to be vertical rather than horizontal. For example, while the Passing Breeze painting has the proper impassible tiles like this :
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A few others (can confirm this is an issue with both the Spell Gems and Color of Magic paintings at least) have the impassible areas like this :
The end result is you can walk through half the painting assuming it’s not on a wall, but even if you DO have it on a wall, there’s an invisible, impassible block one tile under the left-hand side of the painting.