Icon not showing

How To
1

Dear community, I would like to place an icon to indicate an outgoing link into a rich text element. So I chose an appropriate icon and added
<i class=“fas fa-arrow-up-right-from-square”
to the text part of the element. In preview mode, the icon shows neatly, but it doesn’t online. I cannot figure out what might be the reason. Help is very much appreciated.

2

you can use some css to do it globally as follows

article a[href^="http"]::after,
article a[href^="https://"]::after
{
  content: "";
  width: 11px;
  height: 11px;
  margin-left: 4px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' fill='currentColor' viewBox='0 0 16 16'%3E%3Cpath fill-rule='evenodd' d='M8.636 3.5a.5.5 0 0 0-.5-.5H1.5A1.5 1.5 0 0 0 0 4.5v10A1.5 1.5 0 0 0 1.5 16h10a1.5 1.5 0 0 0 1.5-1.5V7.864a.5.5 0 0 0-1 0V14.5a.5.5 0 0 1-.5.5h-10a.5.5 0 0 1-.5-.5v-10a.5.5 0 0 1 .5-.5h6.636a.5.5 0 0 0 .5-.5z'/%3E%3Cpath fill-rule='evenodd' d='M16 .5a.5.5 0 0 0-.5-.5h-5a.5.5 0 0 0 0 1h3.793L6.146 9.146a.5.5 0 1 0 .708.708L15 1.707V5.5a.5.5 0 0 0 1 0v-5z'/%3E%3C/svg%3E");
  background-position: center;
  background-repeat: no-repeat;
  background-size: contain;
  display: inline-block;
}
3

Sorry, but without any further explanation I don’t understand what I am doing there.
Maybe there are other ways to use?

Why isn’t it enough to add the shortcode to the text? I used to do so in previous projects and never had any problems.