Use fiddler to automatically modify the content returned by the specified connection.
1. Download and install fiddler packet capture software
2. Turn on fiddler (the principle of packet capture is actually that we visit the real website through fiddler, an intermediate proxy, so the data transmitted by the website and this machine is visible to fiddler, and of course its data can be changed. Whether it is before or after the request, fiddler will open port 8888 as a proxy by default to proxy all connection requests of the machine. Visit 127.0.0.1: 8888 to view the port. For this reason, you need to pay attention if your own browser has its To use the designated proxy, it needs to be disabled, otherwise the request in the browser cannot be captured. For example, some circumvention plug-ins are like this, so you need to disable it, and you need to confirm it yourself.
3.
The shortcut key f12 is to turn on or off the monitoring.
The following is to modify the returned content of the request to connect to www.example.com/test.html.
