if you have S3d you can add one yourself to see what effect it would achieve. It's much easier to do it in 3d that doing it in the menu1024.ini file. Just find a suitable 3d object (or add one) in the interior DAT files and link it to a Focusable3DObj modifier in the SIM file. For the command, add "Toggle_TDC_autoupdate". Then see what it actually does for US subs

. I'd do it myself but I've modified the menu.ini so much for german subs that us subs crash on me

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