@jonas Apologies. I didn't get any notification that you'd asked other questions so didn't see this until now. Looking at your conversation in #1582 it sounds promising that you may have tracked it down with brilliant help from jirislaby (Kudos, jirislaby. This has been driving me nuts! 🐵 )
If I see any further issues after upgrading to a release with the fix in I'll let you know.
Many thanks to you both.