I've finally found someone else who's seen this behaviour! I've noticed this too, and I found (in my case anyway) that Bing/Outlook seems to Rot13 the keys of

I've finally found someone else who's seen this behaviour! I've noticed this too, and I found (in my case anyway) that Bing/Outlook seems to Rot13 the keys of the query parameters - is this what you're seeing too?