Go to VS/DR YAML edit page.
Do some changes.
Hit Cancel button.
Confirmation appears "You have unsaved changes, are you sure you want to leave?"
Click on OK.
It will switch to Overview page.
But the YAML page will contain the changes. And marked "*" as an edited page.

Original Issue:
https://issues.jboss.org/browse/KIALI-3251

This is affecting OpenShift ServiceMesh 1.0 GA.
It will be resolved in OpenShift ServiceMesh 1.0.1.