Comment 2 for bug 1809913

The Event Loop is still running:

```
Thread 1 "pcbnew" received signal SIGINT, Interrupt.
0x00007ffff60d8c21 in poll () from /usr/lib/libc.so.6
(gdb) backtrace
#0 0x00007ffff60d8c21 in poll () at /usr/lib/libc.so.6
#1 0x00007ffff54e7540 in () at /usr/lib/libglib-2.0.so.0
#2 0x00007ffff54e85c2 in g_main_loop_run () at /usr/lib/libglib-2.0.so.0
#3 0x00007ffff5add2bf in gtk_main () at /usr/lib/libgtk-3.so.0
#4 0x00007ffff7841c46 in wxGUIEventLoop::DoRun() () at /usr/lib/libwx_gtk3u_core-3.0.so.0
#5 0x00007ffff738ebae in wxEventLoopBase::Run() () at /usr/lib/libwx_baseu-3.0.so.0
#6 0x00007ffff7353517 in wxAppConsoleBase::MainLoop() () at /usr/lib/libwx_baseu-3.0.so.0
#7 0x000055555558af05 in APP_SINGLE_TOP::OnRun() (this=0x5555556b5470) at ./kicad-source/common/single_top.cpp:186
#8 0x00007ffff73db4c8 in wxEntry(int&, wchar_t**) () at /usr/lib/libwx_baseu-3.0.so.0
#9 0x0000555555585f30 in main(int, char**) (argc=1, argv=0x7fffffffda18) at ./kicad-source/common/single_top.cpp:260
```

I suspect the creation of an additional wx.App() could be the reason for the problem. I created an issue on wxPhoenix to clarify how to correctly instantiate a wxPython frame based on a c++ parent https://github.com/wxWidgets/Phoenix/issues/1126