I've written an application embedding Teams into a Vue application with a backend that calls the graph api utilizing application level authentication and able to get most the data needed (not presence, but that's a different issue). One piece I'm not able to retrieve are the files for the images that are embedded into the messages, commonly refered to as "in-line images". They are not attachments, they images coppied or inserted into the message.
The "src" of these images look like "https://graph.microsoft.com/v1.0/teams/[TEAM ID] /channels/[CHANNEL ID]/messages/[MESSAGE ID]/replies/[REPLY ID]/hostedContents/[LONG GUID]/$value\".
Using application level (not delegated level) permissions, how can I get these image files? And if not available, oh, that should be a feature added.