Facebook vice president of messaging products David Marcus announced in a response to a tweet that a bug causing the Android application to drain devices? batteries has been resolved.
According to Marcus? tweet (embedded below), restarting the app should remedy the issue.
@bestsportnascar @alxpap issue was isolated and fixed server side. If you restart Messenger the problem should be gone now. Very sorry. — David Marcus (@davidmarcus) January 10, 2017

Marcus suggested in another tweet response that users currently on beta versions of Messenger should use the standard version.
Readers: Have you noticed any battery issues on your devices due to Messenger"
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