I was looking for it for a while, but couldn't find a way to enable the test coverage features in the Rider Unit Test tool window. https://www.jetbrains.com/help/rider/Unit_Tests_Coverage_window.html
2 Answers
The keyword is dotCover, you need to enable it manually in File => Settings => Plugins => search for "dotCover" and enable it.
Looking at my current rider (2022.2.1 build #RD-222.3739.37 from 8th Autust 2022), this has moved now to File => Settings => "Build, Execution, Deployment" => dotCover.
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