> From: Elias Mårtenson <lokedhs@gmail.com>
> Date: Fri, 8 Sep 2017 11:00:42 +0800
>
> As it turns out, ‘call-process’ hangs all of Emacs while the external program is run.
No, it hangs the calling thread, and the other threads wait for the
calling thread to yield. To avoid that, use start-process instead.
This is not a bug.