Searches in Chrome Omnibox randomly use Yahoo instead of Google

I tracked this problem down to the Chrome extension "Ratings Preview for YouTube" (extension has been removed from the Chrome and Firefox add-ons store), as I was having the same problem and it was driving me nuts. I used the LinkResearchTools extension on Chrome to log redirects and found my Google redirects were going to:

https://searchingcafe.com/?a=gsp_dventures_00_00&q={original query}

Which then were redirected to:

https://search.yahoo.com/yhs/search?hspart=dcola&hsimp=yhs-001&type=gsp_dventures_00_00&param1=1&param2=cat%3Dweb%26sesid%3D3147d16554fc40d80a8319989e89c2b7%26ip%3D98.206.52.10%26b%3DChrome%26bv%3D80.0.3987.149%26os%3DWindows-10%26os_ver%3D10.0%26pa%3Dgencoll12%26sid%3Dd5630a969f5ff68effba73db31a6971d%26abid%3D%26abg%3D%26a%3Dgsp_dventures_00_00%26sdk_ver%3D%26cd%3D%26cr%3D%26f%3D%26uref%3D&p={original query}

I was able to use this to find a recent Reddit post describing how "Ratings Preview for YouTube" had started doing these redirects for other people in Firefox; I was using this extension on Chrome so I disabled it, haven't had the problem since, and am now using the extension Thumbnail Ratings Bar for YouTube.