The creator of this extension also makes DeArrow [1]. It replaces the clickbait thumbnails and titles with less annoying ones. I highly recommend it.
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I'm using one that just decapitalizes and uses a random frame thumbnail from the middle, which is okay.
"DeArrow is an open source browser extension for crowdsourcing better titles and thumbnails on YouTube. The goal is to make titles accurate and reduce sensationalism. No more arrows, ridiculous faces, and no more clickbait.
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There are currently 64,634 users who have submitted 230,432 titles and 107,027 thumbnails."