Finally I figured this out.
Its because I don't have
libpng-dev installed on my fresh installation of Ubuntu.
This is required by
pngquant-bin, which is required by
laravel-mix. This somehow disturbed the installation of
shebang-command and 'laravel-mix`.
$sudo apt install ligpng-dev And on laravel project $ rm -rf node_modules $ npm cache clear $ npm install $ npm run dev