Rated 5 out of 5 stars
Dear John, I follow the other comments, that this is a great addon for accessing Google mail.
It supports invitations. I have not found other addons with this capability.
I'm also sorry, that other users do not respect your work for a free addon. Please listen to the users which are glad to have a running tool, and not to the others.
And please do not skip the Google support in the future at all; keep it as now as an unofficial option, which has to be activated per keyword. This saved my day.