One issue I had with elm-spa architecture was going from one Page to another with information that couldn’t be encoded in the URL. I think part of that problem was the directionality of that information, where one goes from URL to message to state. I was wondering if this pattern could reverse the direction and go from message to state to url.
What I mean by reducing complexity is that personally I always find the onUrlRequest and onUrlChange options in Browser.application pretty confusing. Thankfully it’s the sort of thing one usually sets up at the beginning and then doesn’t mess with much, but I feel that the routing APIs could use a bit of streamlining.