Video blinks momentarily to black --- but only in YouTube

I recently re-installed Win11 and all updates with no problems. All devices and hardware is working as expected. However, whenever I am watching a YouTube video, I will get a momentarily "blink" to black that lasts less than 1/2 second. This reoccurs every 3-5 minutes. I have confirmed that it does NOT happen when watching my own home-made MP4 videos or any other commercial MP4 or MPG file. The face that it happens only while on YouTube would tend to mean its their problem. But if I am the only person having this YouTube problem then the problem must be one my end, especially considering that the problem never existed prior to my re-install. Its very doubtful that its a buffering problem because modem speed thru Spectrum is about 400 Mbps.

Its not a major problem but more of an annoyance. Besides its the challenge of figuring it out that entices me. Anyone got any ideas where I should be looking for an answer?

I've seen the same at times on my 25Mbps Wireless DSL and chalk it up to anything streaming can have that happen, probably is the buffering from their site to the user's computer. It's affected by the users' Internet service/connection and all the other Internet servers the signal goes through to get from the source to the destination. Frequently letting it finish then restarting helps.

Try disabling hardware acceleration in your browser.
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