I know that somebody here on the list was stating they where getting copies of their posts coming back to them which they didn't like. You can indeed stop this by first logging into  groups.io and then go to your profile page which is a drop down window under your name your using. In there you will see  which is after Post preference.  My Posts  uncheck the box that states  I always want copies of my own message. And that's it you should now not receive your own copy. Of course that setting goes for all groups.io But at least each of us could make that choice.