iMip Error : ...method "COFIRMED" is not supported

I use Google Business Gmail as my mail provider.
I am a new user of about a week, running Version 8.2.1193 (fb1a574) on Win10.

I am seeing this error…

I just got it now, after doing a search.

I can click on the OK button and I don’t see any ill affects, but is a minor irritation.

Anyone got any ideas?

It appears to be related to specific mails, and not the fact that I searched.