Will not run in Production

[JonoHall]

Scratching my head on this one, I hope someone can help.

My configuration works perfectly in development mode with the "enabled: true" switch, but fails to run in production (exactly the same environment just running "npm run development" and "npm run production").

Configuration:

const mix = require('laravel-mix');
require('laravel-mix-purgecss');

mix.js('resources/js/app.js', 'public/js').vue()
    .postCss('resources/css/app.css', 'public/css')
        .options({
        postCss: [require('postcss-import')],
        postCss: [require('tailwindcss')]
    })
    .purgeCss({
        enabled: true,
        safelist: [
            /^(bg-)(grey|red|yellow|green|blue|indigo|purple|pink)-(100|800)$/, 
            /^(text-)(grey|red|yellow|green|blue|indigo|purple|pink)-(100|700)$/
        ]
    })
    .webpackConfig(require('./webpack.config'))

if (mix.inProduction()) {
    mix.version();
}

Results:

Running on dev. Result expected, CSS not minified.

npm run development
css/app.css │ 3.94 MiB

Running on dev with "enabled: true" switch. Result as expected, CSS minified, safelist respected.

npm run development
css/app.css │ 42.8 KiB 

Running on production. Result not expected, CSS minified, safelist not respected.

npm run production
css/app.css │ 26.7 KiB 

Any idea what's going on here?