[Bug]: External applications cannot access the server running in Termux on Android 16

[nextincn]

Problem description

On Android 16, when running a server program like nginx or SingBox proxy service within Termux, other apps cannot access this server if Termux is running in the background.
However, if Termux is switched to run in the foreground, other applications can access the service normally.
Additional information: Termux has been allowed to run in the background, and there are no restrictions in battery policy. Everything worked fine before upgrading to Android 16.

Steps to reproduce the behavior.

1. Create and run an Nginx server in Termux
2. Switch Termux to run in the background
3. Open a browser and attempt to access the Nginx server; access fails
4. Switch Termux to run in the foreground; the browser can then access the Nginx server normally

What is the expected behavior?

When Termux is running in the background, other applications can access servers running within Termux.

System information

• Termux application version: v0.119.0-beta.3
• Android OS version: Android 16 (One UI 8)
• Device model: Galaxy S24 Ultra

[agnostic-apollo]

Make sure battery optimization are disabled for termux.

Otherwise could be related to termux/termux-api#638 (comment)

[nextincn]

Make sure battery optimization are disabled for termux.

Ensure Termux is unrestricted.