(works only in the codecademy site, but you might get the idea)
In the composer, not all of these links look live. After you submit the post they appear fine. If you go back into the composer they will not look live again.
The ones that aren’t showing as live have this class (in the composer):
class="hashtag hashtag-tested tag-hashtag-tested"
The ones that do show live have:
This is an image demo:
Note that only the first two are showing live (clickable). But when you submit the post, they all appear live.
Credits to @AlbionsRefuge for the initial draft