In reply to Removed User:
I went down the 'IT response #1' route, and re-booted the Android device. Problem solved.
It used to work with the version of Chrome I'm running. So it should have continued to work with the unchanged version. Therefore, it wasn't an issue with the version of Chrome. It must have just got itself a bit confused.
I upgrade software in light of update notes and user reviews. Google app user reviews have been showing a downward spiral recently, since they seem to be letting their software developers play for no good reason, removing features, breaking others. I have a 'sacrificial machine' I use to evaluate updates, and roll out 'stable versions' to my other machines.