Yesterday, with Post Toolbar deactivated, the problem returned. I eventually found that deactivating Front End User, made everything happy again. I reactivated Post Toolbar once more.
This morning I found it wasn’t working once again, so I deactivated Post Toolbar for a moment and then reactivated it. Everything hunky dory once again.
What sort of issue would cause this problem to be intermittent in this way?
Assuming it is a jQuery issue, is this something that can be fixed or is it a case of choosing different plugins?