Doctype Duplication Broken [v15]

Is it just me or has anyone noticed that doctype duplication is broken in version 15? When you duplicate a doctype it returns blank and if you try to save the duplicated doctype it kills all the open erpnext browser tabs.

In version 15, the development branch is working fine for me. I haven’t encountered any issues with doctype duplication

Yes, I have the same problem too with ERPNext: v15.23.3 (HEAD)