URL: https://www.facebook.com/messages/e2ee/t/

Browser / Version: Firefox 121.0
Operating System: Windows 10
Tested Another Browser: Yes Chrome

Problem type: Something else
Description: Facebook Messenger encrypted chats do not allow voice or video calling on desktop and mobile Firefox
Steps to Reproduce:
Firefox 121 Desktop Windows 11: In encrypted Facebook Messenger chats at https://www.facebook.com/messages/e2ee/t/ the phone and video call buttons are missing, see image below.
In non-encrypted Messenger chats such as group chats located at https://www.facebook.com/messages/t/ the phone and video call buttons are still present. I have not tested to see if the buttons actually work.

Firefox 121 Mobile Android 13: While in desktop site mode, in encrypted Facebook Messenger chats at https://www.facebook.com/messages/e2ee/t/ the phone and video call buttons are missing.
In non-encrypted Messenger chats such as group chats located at https://www.facebook.com/messages/t/ the phone and video call buttons are still present. I have not tested to see if the buttons actually work.

Chrome 120 Desktop Windows 11: In both encrypted and non-encrypted Facebook Messenger chats at https://www.facebook.com/messages/e2ee/t/ and https://www.facebook.com/messages/t/ the phone and video call buttons are there. I have not tested to see if the buttons actually work.

View the screenshot

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