When you want to create codecoverage report with phpunit, you need to have XDebug installed otherwise you get just error "No code coverage driver is available". I successfully installed it on Windows but I had lot of issues installing it on MacOS.
Git is something that most of us use daily, though there are functions / commands you do not use but still may help in some situations.
Have you ever heard about yarn resolutions? It is not something you would use everyday, but it is definitely useful.
The first thing you read about setState - it is asynchronous. I understand it but still did not realize a couple of things.