From the Reddit comments: This extension can block domains from Google search and it's made by Google. https://chrome.google.com/webstore/detail/personal-block

From the Reddit comments: This extension can block domains from Google search and it's made by Google. https://chrome.google.com/webstore/detail/personal-blocklist-by-goo/nolijncfnkgaikbjbdaogikpmpbdcdef?hl=en https://chrome.google.com/webstore/detail/personal-blocklist...