[Feature Request]: Show 404 Error Page for Invalid URLs

[RachitSahu26]

This issue will handle situations where users enter an invalid URL and display a custom 404 error page instead of redirecting them to the homepage.

[github-actions]

👋 Thank you for raising an issue! We appreciate your effort in helping us improve. A maintainer from Dataverse will review it shortly. Stay tuned!

[multiverseweb]

@RachitSahu26 the custom 404 error page already exists here. But it is not opening when someone clicks an invalid URL. Maybe there is some issue in file positioning (path). Can you fix it please? I'm assigning level1 for the same. Don't forget to update the file paths used for css accordingly.