Just got invited to a chat and received the notification on Stack's INBOX
Once clicking on it in, i can the transcript with time in UTC which is one hour before my time zone
Then i click join room and the time is as expected (my timezone)
In transcript you see time in UTC, but when you enter the room you see local time.
Showing time in UTC is very common here for content rendered on serverside. Server doesn't know your local timezone. And the other thing is that rendering same time for all users simplifies caching.
This is not a bug. While chat will display your local time correctly when you are in the actual chat room, the chat transcripts shown in your inbox are displayed in UTC time. That is what you are seeing here and it is by design.