>>> new mw.Uri().toString()
"http://127.0.0.1/wiki/Main_Page"
>>> window.history.pushState({}, document.title, 'http://127.0.0.1/foo')
undefined
>>> window.location.href
"http://127.0.0.1/foo"
>>> new mw.Uri().toString()
"http://127.0.0.1/wiki/Main_Page"WTF?
Seems to be because defaultUri is cached once and used forever in the mw.Uri constructor.