Enabling the interact key in game has caused issues for quite some time with targeted buffs and heals either going on NPCs or being unable to be self-casted if you are facing an NPC or item that cannot be interacted with (I’ve reported this before and the issue still persists). However, I only noticed recently that it also affects emotes. If you have the “enable interact key” option set and are facing something you can interact with, it will automatically put that target as the target of your emotes.
For example, you kill a rare mob, loot it, hit escape so that the mob is no longer selected. You type /thank to thank everyone around you that helped you kill it but you actually thank the mob you killed because you are still facing it.
If you are facing an NPC you can interact with and you type an emote, it automatically adds the NPC to your emote.
If you are facing an item you can interact with and you type an emote, it automatically adds the item in your emote.
It does not add players automatically to emotes if you are facing them.