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Why does the UWP app disable the loopback network by default?
In short, the reason is the security concern.
Loopback is the process of communicating with a network server listening on localhost (the loopback address).
To maintain security and network isolation, loopback connections for IPC are blocked by default for packaged applications.
You could find more information here: UWP- Interprocess communication (IPC)
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