Facebook is cool and people keep checking their profiles just to se what going on. Notifications help you know who has commented, tagged or messaged you. all the other notifications such as app invites, groups notifications are useless for a lot of people.

Also, people add you in groups without your permission, which  is quite annoying.

Here are two thing you can do

You can either turn off the notification of leave the Group.

To Turn off the Notifications from Group, Go to the group and click on edit settings on top right hand side.   

Or to leave the Group, simply Click on Leave Group and confirm.

You can also turn off all the email notifications from Facebook that give a lot of headaches to clean the inbox.

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