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Close and/or Mute YouTube ads automatically!
1.4.3 hopefully fixes this issue, I started experiencing it too. It looks like in some scenarios YouTube will load up videos in the background which have their own mute button. The script was just choosing the first one it found but not it tries to be a bit smarter.
v1.4.2 is working but not with the mute button. Sometimes the ad videos got muted and sometimes they still making sound