Hi Dan,
Yes, upgrading is on the cards for this client but it’s a big site so it takes a little while to prepare for. I have however got a dev version running in a sub domain of the same server and will be running a few tests myself to try and recreate the problem. If I can recreate it, I’ll upgrade to 2.3.1 and see if that does the trick. If so, we’ll move forward our plans to upgrade the live site and let you know.
As for your other questions: It has happened a few times to this client. Initially on 2.1.3 and now on 2.2.2. I can confirm that they’re using Windows in their office but the version varies from machine to machine. The site has a few different admin users, so the browser also varies but we have encouraged them towards Chrome and away from IE. Last time this issue occurred, the user was running the latest stable version of Chrom on Windows 7.
If there’s anything else I can tell you which may be helpful, please let me know.
Sam