Instagram Photo Audio Enabler by Wilson Júnior

Instagram's mobile app plays the song attached to a photo or carousel post. The
web client renders the same post in silence, because it offers no interface for
a track that is not attached to a video.

The data is already there. When a post is opened on the web, Instagram fetches
the audio URL, the start offset and the clip length, then never uses them. This
extension uses them.