Local host:8888 is unreachable

[CHERYLMAISELOBO]

I can't reach localhost:8888 but I can reach localhost:8025. How can I fix this issue?

[fhkzero]

The same thing happened to me. After solving Challenge 3, I went to the home screen and was faced with a white screen. Everywhere I went there was a white screen. I restarted the environment but it didn't help. The solution is simple, if you are using mozilla firefox, click the Clear Data button under Cookies and Site Data and delete cookies. That's what I did and it fixed it.