RemixIconEx.Media.fullscreen_exit

You're seeing just the function fullscreen_exit, go back to RemixIconEx.Media module for more information.
Link to this function

fullscreen_exit(icon_css_class \\ "icon")

iex> Elixir.RemixIconEx.Media.fullscreen_exit()
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" class="icon">
  <path d="M18 7h4v2h-6V3h2v4zM8 9H2V7h4V3h2v6zm10 8v4h-2v-6h6v2h-4zM8 15v6H6v-4H2v-2h6z" />
</svg>

example usage

svg.icon {
  width: 96;
  height: 96;
}