The voice message is uploaded to rupload.facebook.com/messenger_audio/<entity>
through MessengerMediaUpload, the one owner of a media upload's wire (the
header set the foreign host needs, the upload slot, the entity headers and the
owner's error mapping). The entity name is the app's
<upload id>_0_<signed tail>, and the form repeats the upload id as
upload_id.
The broadcast is the app's (direct-message-voice 123): no
is_x_transport_forward, no Meta AI field and no action flag — the form's own
order, with the waveform after the navigation chain.
Send a voice message.
The voice message is uploaded to
rupload.facebook.com/messenger_audio/<entity>throughMessengerMediaUpload, the one owner of a media upload's wire (the header set the foreign host needs, the upload slot, the entity headers and the owner's error mapping). The entity name is the app's<upload id>_0_<signed tail>, and the form repeats the upload id asupload_id.The broadcast is the app's (
direct-message-voice123): nois_x_transport_forward, no Meta AI field and no action flag — the form's own order, with the waveform after the navigation chain.