Unsure if it counts as a bug, but if you quit to main menu after choosing a card and before it sends you back to the shop, you will be able to change your choice. It feels against the spirit of cards like wheel of fortune and emperor (cards that have randomness) to be able to check whether or not the card works in your favour or not. It removes all of the risk that wheel of fortune comes with.
#You are able to redo arcana and spectral packs
sage tangle
You should be able to change your mind before the effect shows (for example the emperor showing what tarots it gives you or wheel of fortune saying 
) but after that, your choice is saved, so you can't change your mind based on whether it worked or not.
keen perch
You should be able to change your mind before the effect shows (for example the ...
Because of that my game crashed. #1222997475393011803
keen perch
You should be able to change your mind before the effect shows (for example the ...
you can also use it with wheel of fortune, if you're fast enough when it "nope"s you cn choose an other thing
restive pine
If you do this with packs from tags you get softlocked, but other then that this has existed since the january demo. The only difference has been you have to go to main menu instead of continuing run