Issue with minifying not pseudo-class alongside using selector inside it

[amerllica]

Explanation

I have searched and didn't find this bug and its solution. I'm using html-minifier-terser and this bug happened inside it, this library is using clean-css version 4.2.3 and inside this when we are using *:not(div *) selector, after minifying it transform to this *:not(div*) and because div* --there is no space between v and *-- has no meaning for any kind of browsers, whole the css system faced error and no css is existed in system.

• finally, be nice and have fun!

Environment

• clean-css version - npm ls clean-css: 4.2.3
• node.js version - node -v: 16.3.0
• operating system: macOS big sur

Configuration options

var CleanCSS = require('clean-css');
new CleanCSS({});

No config. all configuration is on default settings.

Input CSS

*:not(div *) {
  color: red;
}

Actual output CSS

:not(div*){color:red}

Expected output CSS

:not(div *){color:red}

[amerllica]

I tested the version 5.1.3 and this issue is fixed in this version.