Let me guess, you're using Gmail or another "web mail" on Thunderbird? Yeah there's a lot of artificial lag generated by Google or some bad process along the wa

Let me guess, you're using Gmail or another "web mail" on Thunderbird? Yeah there's a lot of artificial lag generated by Google or some bad process along the way. I get the same lag in Gmail, but they hide it behind CSS changes. In Thunderbird they actually show you the inherent lag (until it's ACTUALLY changed state). It's a Gmail thing though and most email connections are blazing fast. Here's a test to run on Gmail web client: Mark an email unread or do anything that changes state. Now click the email, as to read it, and then close your browser. It will not let you because it's still "lagging" in the background for you. It's dreadful.