Thank you for your feedback and a detailed explanation of the issue. We can confirm that currently there is an issue when using Fiddler alongside VPN through Cisco AnyConnect. The team is currently estimating the issue and you could expect a fix that will provide compatibility with Cisco Anyconnect in one of the upcoming releases of Fiddler Everywhere.
Meanwhile, try to resolve the issue by applying this solution.
Once again thank you for your interest in Fiddler.
Progress is here for your business, like always. Read more
about the measures we are taking to ensure business continuity and help fight the COVID-19 pandemic.
Our thoughts here at Progress are with those affected by the outbreak.