I add a fetch event listener like this

self.addEventListener( 'fetch', fetch )

and here is my fetch function

const fetch = e => {
    console.log({e})
    if ( !e.request.url.startsWith( self.location.origin ) || e.request.method !== 'GET' ) return

    const save = async res => {
        const cache = await caches.open( dynamic )
        cache.put( e.request, res )
    }

    const process = async cached => {
        if ( cached ) return cached
        const res = await fetch( e.request.clone() )
        if ( res ) await save( res.clone() )
        return res
    }

    e.respondWith( caches.match( e.request ).then( process ))
}

When I look at the event thats being passed in, I expect a fetch event but this is what I see

Its printing a request object after the correct Fetch event. When i try to access the url, it will of course throw an error as it will effectively be doing request.request.url