I don't really know why but I felt like I should be able to do that.
Install the following script with your favorite Userscript manager https://gist.github.com/eramdam/07e0060d0f6dc40dd480058dad226d24/raw/fbd4145ca3d614f5fa85cf37d6477ecadbe0d7e6/scroll-to-top-cohost.user.js
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