UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.92 Safari/537.36

Steps to reproduce the problem:
1. Add urls or domains to be request blocked.
2. Run an audit of the page.

What is the expected behavior?
The request urls or domains I blocked should not be downloaded or parsed in the Audit.

What went wrong?
The blocked requests are still downloaded and parsed in the Audit.

Did this work before? N/A 

Chrome version: 69.0.3497.92  Channel: stable
OS Version: OS X 10.13.5
Flash Version: 

I wanted to measure how much time GTM added to our websites loading time, Audit is a nice tool for measuring performance for example. But since the request blocking doesn't work and GTM adds a lot of other scripts I couldn't really measure it.

Our GTM has a lot of other third party tracking scripts added inside it.