simplebrowser crashes when passing command line argument "-type=1"

[Problem]

Build and run the following official demo with command line arguments "-type=1"

Qt5.8.0\Examples\Qt-5.8\webenginewidgets\simplebrowser

then I get a crash. But if I change the option to "-typeeee=1" or sth. like "-typo=1", things are ok.

[Question]

We have a need to pass "-type=1" to our application but why the command line "-type=1" can cause the QtWebEngine to crash? Does "-type" is a hidden special option for WebEngine? I don't find any official docs to describe this option right now.

[Expected]

 No crash at all, and -type is free to use if possible.