Google Chrome browser uses 'Quick UDP Internet Connections' which MWG does not support.
So it does not block gmails.
Please let me know how to solve this issue.
I would assume that Chrome falls back to plain HTTP if the UDP traffic is blocked. Can you verify the UDP traffic is not allowed for that client?
If the UDP traffic is blocked all traffic should go to MWG. MWG is not capable of filtering the UDP traffic, it does not even see it usually.