Hola Alvaro,

A small problem becuase Font Awesome 5 does not have a NEW Twitter icon, only old one.

I know that you are not afraid challenges, so please download Font Awesome 6 Free package, Unzip it. And replace/override those files:

• templates\edulif\css\font-awesome.min.css
• and all files here: templates\edulif\fonts

Then use that Custom CSS

.splms-icon-twitter::before {
  content: "\e61b";
  font-family: "Font Awesome 6 Free";
  font-weight: 600; }

It should help :) in theory.

• Helix Ultimate >> https://www.joomshaper.com/documentation/helix-framework/custom-code-css-js-meta
• Helix3 >> https://www.joomshaper.com/documentation/helix-framework/helix3/custom-css-header-code#how-to-use-custom-css

In general, in Custom CSS area. You don't need to edit any file.

font-splms.css is the file where is the icon inside LMS component

has his own code for font family font-family: 'splms'; src: url('../fonts/splms.ttf?9e6gz9') format('truetype'), url('../fonts/splms.woff?9e6gz9') format('woff'), url('../fonts/splms.svg?9e6gz9#splms') format('svg'); font-weight: normal; font-style: normal; font-display: block;

and code for twitter icon 
}

.splms-icon-twitter:before { content: "\e65d"; }

line 327 to 330

but can not upgrade this file to awesome font 6 free

Do not edit component files! It does not make sense.

As I said before you can also use alternative method

1. download image file (Save Image as) >>

2. Upload to /images folder

3. Then use that Custom CSS:

.splms-icon-twitter::before {content: url("/images/x.png"); display: inline-block;height: 16px;}