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How do I leave a group I no longer wish to be a part of?
If you go to the groups page you will see your name and avatar along the top bar next to the group’s avatar and name. When you hover over it, it will say "member" clicking this will give you a drop down, and the very last option will be "leave this group". Selecting this option will remove you from the group.
Please note that if you leave the group, the group will still remain on your watch list. If you no longer wish to receive messages from the group you will need to go to your manage watchers page and remove the group.