@buzztone — many thanks for the suggestions.
In the end, I turned to the excellent support staff at Elegant Themes, which makes the Gleam theme I use in my website. They made some adjustments to the way the URL appears in the browser address bar, which seemed to fix the problem.
I wish I could be more specific with the technical explanation; alas, I’m a real novice with this stuff.
Regards,
Matthew
