iOS 11 users have been complaining about excessive battery drain on their devices when watching YouTube videos. It was a sporadic issue, with some experiencing heating problems or 10% loss of battery life in just 15 minutes of viewing. Others seemed to experience no issues. Whatever the issue was, Google apparently has found a fix and announced it in today's latest update of the YouTube app.
The fix apparently went live in version 12.44 release two weeks ago, according to Google, but the official announcement is only showing up in 12.45 today. Oddly, "Fixed an issue with battery usage" is the only note on what's new, so if it was fixed two weeks ago, as they claim, it seems odd to release an update just to fix the patch notes.
Whatever the case, Google has been promising a fix since the issue came to light. The problem had also been reported in versions 12.42 and 12.43 of the app, regardless of the iOS version, but became more prevalent after the launch of iOS 11. The company is staying mum on exactly what was causing the problem, but at least now a "hot video" will refer to its content as opposed to what it does to your device.
If you still run into issues, let us know.