Currently, Firefox for Android only sends the page's title to Android's media metadata, and it only sends it every once in a while. Android's media metadata is used to show track info in bluetooth speakers and car stereos paired with the device. Chrome supports this, so I'm currently using it instead of Firefox when listening in my car. It'd also be nice if Firefox for Android supported media session action handlers so I could control more than just the volume with the buttons on my steering wheel.
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