The SPOF (Single Point of Failure) test lets folks see how a site performs when a third-party resource that blocks the initial rendering of the page suddenly hangs (the provider has issues, etc).
WebPageTest also makes it possible to block individual resources from loading, or to block all resources from a given domain.
Let's see how to run a SPOF test. follow WebPageTest: https://twitter.com/RealWebPageTest
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