Description of the issue:
I saw ad on youtube while browsing brave after a long time. 
. I would like to know how that was possible.
Steps to Reproduce (add as many as necessary): 1. 2. 3.
- I played a playlist on youtube and the first video as ad.
- It was a kickstarter ad. All the shields were turned on.
Actual Result (gifs and screenshots are welcome!):
Expected result:
The video should have been played but instead the ad was shown.
Reproduces how often:
Refreshing the page or clicking on the same video didn’t again show the ad.
Operating System and Brave Version(See the About Brave page in the main menu):
Ubuntu 18.04
Version 1.9.80 Chromium: 81.0.4044.138 (Official Build) (64-bit)