There is an app whose developer not publish it on Google.

It updates itself with no big issues on Android below 9, having the "disable install from unknown sources"unmarked on feature control.

On Android 10, the permission of unknown source is set by app and not globally.

There is around 3000 devices in our MC and we have granted manually this permission. After the self installation the permission sets back to denied automatically.

We have sent some scripts to allow the unknown source installations to a app, but could not find one that properly set it on Android 10.

We have already used:

enable_system_app app_name
afw_set_permission_grant_state app_name android.permission.REQUEST_INSTALL_PACKAGES allow
afw_set_permission_grant_state app_name android.permission.INSTALL_PACKAGES allow
afw_set_permission_grant_state app_name android.permission.RESTART_PACKAGES allow

Does anybody know any android.permission to enable Unknown source.

In Android 10 this configuration may be found on Special Permissions screen.