I think this is a bug. When you double-click accidentally on the “Check my code / Submit and continue” button the challenge is saved twice in the timeline. Is there a way to delete the duplicate entry ?
Hello there,
If you hard-refresh the page, does the duplicate go away?
Hello 
It doesn’t work. The duplicate is still there.
Thank you.
If you want, this bug can be reported as a GitHub Issue. Whenever reporting a bug, please check first that there isn’t already an issue for it and provide as much detail as possible.
Otherwise, I will open an issue about this.
Thank you!
It’s the issue 66964