because its MIME type ('text/html') is not a supported code example

Example: Refused to apply style from 'http://localhost:9000/public/css/style.css' because its MIME type ('text/html') is not a supported stylesheet MIME type, and strict MIME checking is enabled.

For me the solution was: instead, app.use(express.static(__dirname + '/public'));

I have used: app.use(express.static(__dirname));

now everything working correctly