favicon doesn't appear
You forgot to serve
silly mistake, here's a working repl:
don't forget to hard refresh
ctrl + shift + r
remember: in express and node, no file is public to the server unless you tell it to
In the head of your web pages try the following tag:
<link rel="icon" type="image/png" href="/favicon.png">
In any case the icon should be sent back from the server if the tag above is not present, as long as the icon file is at the same level as your index.html file.
Note that you do not need a link tag that references the favicon in the index.html page as browsers look for them automatically in the root of the site.