GF wants to hangout with my friend alone

Me (25m) and my gf (24f) have been dating for 3 months already. My friend is visiting me from out of state for one week. We both hanged out with my gf on the first weekend.

During a conversation, my friend mentioned that he liked coffee and then my gf suggested that they should try her favorite coffee spot during the week while I’m at work because she works remotely.

I felt weird about it because it felt like she wanting to hangout with my friend while I’m at work and she should be working too seems like a red flag and I just wanted to get other opinions before I confront her about it.

UPDATE: Thanks everyone for commenting.

I spoke with my gf and my friend about it. My girlfriend agreed that she shouldn’t have mentioned that because she thought about it right after saying it and thought that it might be inappropriate. She also said she wouldn’t like for me to do the same to any of her friends.

My friend thought it was weird also because of the way it came up and is very reluctant about it, he wouldn’t do anything that I’m not comfortable with.

Apologies to anyone that was triggered by my post, I didn’t think about it from a trusting perspective but just about respecting boundaries.