When I mute a group conversation in Messages (by enabling “Do Not Disturb” in the Details screen of the thread), I still get a notification with every new message. This happens regardless of whether everyone in the group is using an iPhone or mixed (non-iOS and iOS). This also happens when my phone is both locked and unlocked.
I am running iOS 10.3.3, but it's been happening for some time. Is there a workaround to fix this?