custom-component.js

//
//  Initialize the MathJax startup code
//
require('mathjax-full/components/src/startup/lib/startup.js');

//
//  Get the loader module and indicate the modules that
//  will be loaded by hand below
//
const {Loader} = require('mathjax-full/js/components/loader.js');
Loader.preLoad(
  'loader', 'startup',
  'core',
  'input/tex-base',
  '[tex]/ams',
  '[tex]/newcommand',
  '[tex]/configmacros',
  '[tex]/action',
  'output/chtml', 'output/chtml/fonts/tex.js',
  'ui/menu'
);

//
// Update the configuration to include any needed values
// (we set the mathjax path explicitly, since it defaults
//  to the location from which this file is loaded)
//
const {insert} = require('mathjax-full/js/util/Options.js');
insert(MathJax.config, {
  loader: {
    paths: {
      mathjax: 'https://cdn.jsdelivr.net/npm/mathjax@3/es5'
    }
  },
  tex: {
    packages: {'[+]': ['ams', 'newcommand', 'configmacros', 'action']}
  }
}, false);

//
// Load the components that we want to combine into one component
//   (the ones listed in the preLoad() call above)
//
require('mathjax-full/components/src/core/core.js');

require('mathjax-full/components/src/input/tex-base/tex-base.js');
require('mathjax-full/components/src/input/tex/extensions/ams/ams.js');
require('mathjax-full/components/src/input/tex/extensions/newcommand/newcommand.js');
require('mathjax-full/components/src/input/tex/extensions/configmacros/configmacros.js');
require('mathjax-full/components/src/input/tex/extensions/action/action.js');

require('mathjax-full/components/src/output/chtml/chtml.js');
require('mathjax-full/components/src/output/chtml/fonts/tex/tex.js');

require('mathjax-full/components/src/ui/menu/menu.js');

//
// Loading this component will cause all the normal startup
//   operations to be performed when this component is loaded
//
require('mathjax-full/components/src/startup/startup.js');