When to use the Network panel
In general, use the Network panel when you need to make sure that resources are being downloaded or uploaded as expected. The most common use cases for the Network panel are: Making sure that resources are actually being uploaded or downloaded at all. Inspecting the properties of an individual resource, such as its HTTP headers, content, size, and so on.
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Performance
If you're looking for ways to improve page load performance, don't start with the Network panel. There are many types of load performance issues that aren't related to network activity. Start with the Audits panel because it gives you targeted suggestions on how to improve your page. See Optimize Website Speed.
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