Permission from manifest doesn't work in Android 6

It completely ignores:

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"/>

So I got exception:

Caused by: android.view.WindowManager$BadTokenException: Unable to add window android.view.ViewRootImpl$W@86fb55b -- permission denied for this window type

It's not even listed:

How should I fix it? Thanks.

EDIT:

It's listed in Configure apps/ Advanced / Draw over other app. So i turn it on and now it works fine, but why there isn't any dialog to ask about permission when i run my app? All perrmissions was turned off by deafult and i need to go to settings and mannualy turn it on?

Thanks to CommonsWare's blog post, I got some clue.

Assuming your code is in Activity or Fragment, check the overlay permission and make a request for it if necessary:

public static int OVERLAY_PERMISSION_REQ_CODE = 1234;

public void someMethod() {
    if (!Settings.canDrawOverlays(this)) {
        Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
                Uri.parse("package:" + getPackageName()));
        startActivityForResult(intent, OVERLAY_PERMISSION_REQ_CODE);
    }
}

Then, re-check the permission for better UX:

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == OVERLAY_PERMISSION_REQ_CODE) {
        if (!Settings.canDrawOverlays(this)) {
            // SYSTEM_ALERT_WINDOW permission not granted...
        }
    }
}