I mean, I see chats as one continuous conversation and unless the conversation has been properly ended, it shouldn’t be necessary even if a night has passed.
I mean, I see chats as one continuous conversation and unless the conversation has been properly ended, it shouldn’t be necessary even if a night has passed.
If you’re talking within the same day, I would consider it fine to continue talking.
…But if you’re talking overnight or longer, I feel like you need a greeting of some kind to acknowledge that the time has passed. I wouldn’t call it rude not to, but it’s an extra pleasantry.