Bottom panel shows the server requests, top panel show server activity. So if a request fails the server will still run it processes to completion. Because we set server to use only one process, it will eventually complete all it’s pending requests and thus, top panel still runs.
Same thing would happen if you closed browser window during upgrade. Sql server still runs til killed or competes it’s pending.
Looks to me in your case a table update was missed. Check upgrade scripts to see where that colume is created and rerun upgrade from there. If I recall, v500 to v501.