Elixir : Delete all comments in Js and CSS files

You are sure it's not the copyright comments that persists. These should not be removed as it makes your product infringing.

What I need is to minify the css, there is a lot of nodeJS tool do that, So I'm asking the way to do with Elixir.

With Laravel-elixir version 6 :

elixir.config.css.minifier.pluginOptions = {
    keepSpecialComments: 0
};

Source : https://github.com/laravel/elixir/blob/master/src/Config.js#L188-L191 and https://github.com/jakubpawlowicz/clean-css#how-to-use-clean-css-api

@kossa i used laravel 5.5, in which file i should put this code

@wowrudy Laravel 5.5 uses Mix so you don't need to do anything, webpack does all these staffs for you. you need to use npm run production

@WOWRUDY - If you are still using Elixir in 5.5 just add it at the top of gulpfile.js, right under the var elixir declaration