Way to tell if a card is already in a trade

Unless I’ve missed something, I think it can be a little tedious going through my previous trades to ensure I’m not offering the same card to multiple people. I’ve already encountered a few times where I traded both copies of a card I had away without realizing because technically I didn’t have only 1 left, I had both, and both trades were accepted.

I think it’d be nice to have a warning before you select a card that’s already in a trade, regardless of copy #, similar to how it warns you that the card is your last copy. Something like:

“This card is currently in another trade. Are you sure you want to add this?”

For people who don’t care so much about it, or don’t want to be annoyed by it, maybe there could be an option to turn off the warning! I’m just tired of constantly checking through every active trade to ensure I’m not offering something I’ve already offered to someone else!