URL: https://www.facebook.com/

Browser / Version: Firefox 139.0
Operating System: Windows 11
Tested Another Browser: Yes Chrome

Problem type: Something else
Description: Facebook Messenger Calls not available in Firefox
Steps to Reproduce:

1. Open Facebook Messenger in Firefox.
2. Select any personal chat.
3. Try to call using the corresponding button.

Actual results:
The button is disabled with the "Voice calling is not supported on this browser" tooltip. See https://www.facebook.com/help/messenger-app/2322144494758524/

Expected results:
A call starts after pressing the button.

View the screenshot

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