How does Messenger integrate with other Facebook services, and are there any limitations to this integration?
Can I use Messenger to make voice and video calls, and what are the requirements for doing so?
Is it possible to customize chat notifications for specific contacts or groups in Messenger?
What security and privacy features does Messenger offer to protect my conversations?
How can I initiate a chat with someone who is not on my friends list in Messenger?
Can I access and use the Messenger service on multiple devices simultaneously, and how is message synchronization managed across those devices?
Does the Messenger service offer end-to-end encryption for all messages, and how does it work?
Are group chats supported on the Messenger service, and is there a limit to the number of participants?
Can I use the Messenger service to send files or images, and are there size limits for these attachments?
How does the Messenger service ensure the privacy and security of my conversations?
