*Be careful there is no "undo" button and deleted messages are not recoverable.
To delete an individual message: open the conversation thread, scroll to the message you wish to delete and long click on the text. A menu will appear above the message and you can choose Delete.
To delete an entire conversation thread: open the Inbox, scroll to the thread you wish to delete but do not click the thread. Instead, click the 3 vertical dots on the right. This will open a menu and you can select the Delete button.
To delete multiple conversations: Long press and hold any conversation (a), Begin selecting conversations and the action (b)
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