It's a white app with a blue message bubble and white lightning bolt inside.


If you aren't signed into Messenger, type in your phone number, tap Continue, and enter your password.
 It's the house-shaped icon in the bottom-left corner of the screen.


If Messenger opens to a conversation, tap the Back button in the top-left corner of the screen first.
, After a second or so, a window with the heading "Conversation" will pop up.
 It's the option at the top of the "Conversation" window.
 Doing so will remove the conversation from your Facebook messages history.
Open Facebook Messenger.
Tap the Home tab.
Scroll to the conversation you wish to delete.

,
Tap and hold the conversation.
Tap Delete.
Tap Delete Conversation when prompted.
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