I am seeing that the call timers inside the Queue buttons get out of sync rather quickly (the Extension button's timer & status are correct, but not always the timers listed inside each Queue button).

You can see in my attached screenshot that Clerk 14 is currently in a call and has been for 8 seconds. The upper Queue button correctly shows clerk 14 is active in a call for 9 seconds (close enough), but the bottom Queue button never stopped counting since his previous call, and now is up to 1:17 and climbing.

I have turned on debug logging with -X 3 and I do see AgentConnected and AgentComplete messages occur as expected when this happens. If I refresh the page in my browser (Chrome), everything is correct again for a short while, but before long I start seeing some of these mismatched timers again.

I am using Asterisk 13 (in which eventmemberstatus is deprecated, but the same events are always sent by default ) with FOP 2.31.15 and I have my manager.conf setup with the event filters described in the installation instructions here:
https://www.fop2.com/docs/installation.php#ConfiguringtheServer

It just appears as though not all of the AgentComplete messages are always being processed, or are only updating some of the Queue buttons but not others for some reason.

I tried cranking up the poll_interval to see if that could work around the problem, but it hasn't helped that I've noticed.

Any thoughts for me? Or any additional information I can provide?

Looking into this more closely, it turns out that it's not just the call timers that are an issue. The member status listed inside the Queue button (DND, on-call, available) becomes incorrect after awhile too.

Again, the data in the member's Extension button is correct during this, but the member listing inside the Queue buttons does not update properly after a while. And again, refreshing the browser window gets things back to normal for a while.

In the following attachment, you can see in the extension buttons that clerk 2 and clerk 3 are actively on a call (which is correct), but one of the queue buttons below incorrectly shows them both as being paused. If I refresh my browser window, then they reflect the correct status in the queue button again... for a while.

I find that doing a "fop2 reload" on the server causes everything to refresh on existing browser sessions, so a possible workaround could be to scheduled automated reloads periodically (presumably there is no harm in doing so).