Issue

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Description

Not specifying player-external-http does not stop streamlink from listening on all interfaces.

This causes a problem on a system where interfaces might change or go down while streamlink is running, where somehow streamlink has passed an ip other than 127.0.0.1 to the player

Expected / Actual behavior

according to the documentation for player-external-http

the server will listen on all available connections instead of just in the local (loopback) interface.

according to the comments create_http_server in main.py

If host is empty, listen on all available interfaces,

which it does do, and in turn when not in external mode, the http server is still listening on all interfaces.

Reproduction steps / Explicit stream URLs to test

Logs

Additional comments, screenshots, etc.