Say you created a new repl called, bob.repl.co (I know this wouldn't be possible, it's just an example), and in the repl you created multiple HTML files, eg. index.html, about.html, hello.html ect.
If you typed in bob.repl.co/hello.html it would take you to that page.
So, I was thinking it would be really cool if you could make your own customised error page, not just the one that pops up made by repl.
So if you typed in bob.repl.co/jeff.html instead of it taking you to this page:
It takes you to a custom error page, designed by you!