If you have items in your object lists that you never look at (for example a Conversation that doesn't apply to you), or you're seeing updates in your recent activities or in your email digests about items you don't care about, you can mute those items. Muting an item hides it and its activity from your view. It's still there; you just won't hear about it anymore. (The only exception is if you're flagged on a message in a muted item, for which you will still be alerted by email based on your notification settings.)
To mute an item:
Open the item.
Click , then select Mute <Object>.
A banner appears at the top, showing that the item is muted.
To unmute an item:
From the navigation menu on the left, select the type of item you want to view (for example, Conversations.
In the Show menu, select Muted.
Click an item to open it.
In the banner showing that the item is muted, click Unmute.
If you dismissed the banner, click , then select Unmute <Object>.