External CSS & JS assets groups with bootstrap and font-awesome support

1.4.1 2018-03-15 10:32 UTC


Create your own css & js groups and add them to your contao theme layouts.

General features

  • Backend Module for external css
  • Backend Module for external js
  • Add multiple CSS & JS groups to contao layout
  • Bootstrap framework support (for css by default, enable within js group)
  • Font-Awesome added by default (availability of all variables and mixins)
  • Elegant Icons can be added (availability of all variables and mixins)
  • Css file caching for production mode (disable byPassCache in contao settings)

External CSS


  • Complete lesscss support, automatically compile all your less files within a external css group to css
  • Observer folders (recursive) within your external css groups
  • Add multiple custom variable files, to overwrite for example bootstrap variables.less (like @brand-primary)
  • make use of all bootstrap mixins and variables within your own less files (See: http://getbootstrap.com/customize/#less-variables)
  • bootstrap print.css support
  • Internet Explorer 6-9 - 4096 css-selector handling (Internet Explorer 6 - 9 has only a maximum of 4096 css-selectors possible per file. Extassets make usage of https://github.com/zweilove/css_splitter ans solve this problem by splitting aggregated files into parts.)
  • all files within $GLOBALS['TL_USER_CSS'] will be parsed within external css groups


Contao 4.0

  1. Install via composer
composer require heimrichhannot/contao-extassets
  1. Add the following to lines to the $bundles array in your app/AppKernel.php
     * {@inheritdoc}
    public function registerBundles()
        $bundles = [
            new ContaoModuleBundle('extassets', $this->getRootDir()),
            new ContaoModuleBundle('haste_plus', $this->getRootDir()),

  1. Clear app chache
bin/console cache:clear -e prod



Attach custom fonts or css libraries to extassets combiner.

// config.php
$GLOBALS['TL_HOOKS']['addCustomAssets'][] = array('MyClass', 'addCustomAssetsHook');

// MyClass.php

public function addCustomAssetsHook(\Less_Parser $objLess, $arrData, \ExtAssets\ExtCssCombiner $objCombiner)
    // example: add custom less variables to your css group to provide acces to mixins or variables in your external css files
    // example: add custom font to your css group
    $objFile = new \File('/assets/components/my-library/css/my-font.css, true);
    $strCss = $objFile->getContent();
    $strCss = str_replace("../fonts", '/assets/components/my-library/'), $strCss); // make font path absolut, mostly required

Font Awesome (http://fontawesome.io/)

Use font-awesome mixins and variables right inside your less files.

// my-styles.less
    content: @fa-var-github;

List of all font-awesome variables, see (https://github.com/heimrichhannot/font-awesome/blob/master/less/variables.less).

Elegant Icon Font (http://www.elegantthemes.com/blog/resources/elegant-icon-font)

Use elegant-icon mixins and variables right inside your less files.

// my-styles.less
    content: @ei-var-info;

List of all elegant-icon variables, see (https://github.com/heimrichhannot/elegant-icons/blob/master/less/variables.less).