I just found out the reason why my Chromebook will no longer install some of those ad-blockers in the Web Store is Google is at war against Ad-Blockers.
They own YouTube and make their money from YouTube ads.

That NOADS ad-blocker is good for some things. But it won't let you play YouTube videos. Or some of my Sports Sites.
So the uBlock ad-block is still the best for Chrombooks right now.

When you click those three dots on the upper right and scroll down the list to Extensions. You see this.

https://www.geocities.ws/bkbrat/Extensions.png

Click that Manage Extensions. There you can either turn off or Remove any ad-blockers or any other Extensions you have.
Then see if you can install this uBlock ad-blocker into your Chromebook. It is the one we are using, and it is still the best for now.

https://ublockorigin.com/

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