UserAgent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.186 Safari/537.36

Steps to reproduce the problem:
Go on Youtube and check comment section to click on a comment with a time realated to the video

What is the expected behavior?
Not be able to ear the sound

What went wrong?
Hi, I am Clément Bétron and i found a problem on YouTube. If I make midstakes in english, excuse me, my mother language is french.

So, to explain the bug, if you go on a video on YouTube (at least with windows 10) with Chrome (or any other browser) and the video is only possible to watch when you have 18 years old or more, you can still have the sound of the video playing in the background. This bug doesn't affect Android or IOS for sure, i tested it also. I don't know if it works on MacOS. 

For that, you only needs to go in the comment section, then if you find a comment or if you write one by yourself that contain a time that shows normally the video timing and starts the video, you can hear the sound of the video even if you don't have the permission to do it normally. This is a bug that could be dangerous for kids for exemple if they could hear inappropriate speakings or sound.

To resolve this problem, you can probably just remove the comment section on a video if the user didn't prove he is over the majority or disable the possibility to be able to do that. The first option isn't a bad choice in my opinion because often, if a video isn't for people under the majority, they should not see the comment section.

I will show you in a little video what i mean, and you could try it by yourself. I filmed thanks to my phone to show you the sound is hearable. On the video, I disconnected from my google account to show you it's possible without authentification.

Thanks and I hope you will appreciate my help, have a nice day.

Clément.

Did this work before? N/A 

Chrome version: 64.0.3282.186  Channel: stable
OS Version: 10.0
Flash Version: 

Hope it will helps