RemixIconEx.User.user_heart

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

user_heart(icon_css_class \\ "icon")

iex> Elixir.RemixIconEx.User.user_heart()
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" class="icon">
  <path d="M17.841 15.659l.176.177.178-.177a2.25 2.25 0 0 1 3.182 3.182l-3.36 3.359-3.358-3.359a2.25 2.25 0 0 1 3.182-3.182zM12 14v2a6 6 0 0 0-6 6H4a8 8 0 0 1 7.75-7.996L12 14zm0-13c3.315 0 6 2.685 6 6a5.998 5.998 0 0 1-5.775 5.996L12 13c-3.315 0-6-2.685-6-6a5.998 5.998 0 0 1 5.775-5.996L12 1zm0 2C9.79 3 8 4.79 8 7s1.79 4 4 4 4-1.79 4-4-1.79-4-4-4z" />
</svg>

example usage

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