Stop Reach Router scrolling down the page after navigating to new page

Building off of @Marcus answer, you can get rid of the jank with useLayoutEffect() instead of useEffect() - this way the scroll action happens after the DOM has been fully rendered, so you don't get the weird "bounce."

// ScrollToTop.js
import React from 'react'

export const ScrollToTop = ({ children, location }) => {
  React.useLayoutEffect(() => window.scrollTo(0, 0), [location.pathname])
  return children
}

Try using <Router primary={false}> which will not focus on the route component.

https://reach.tech/router/api/Router

primary: bool

Defaults to true. Primary Routers will manage focus on location transitions. If false, focus will not be managed. This is useful for Routers rendered as asides, headers, breadcrumbs etc. but not the main content.

WARNING: If you are concerned about breaking accessibility please see this answer: https://stackoverflow.com/a/56996986/428780

I had to use a combination of things to make it work. Even with setting primary={false} there were still cases where the pages would not scroll to the top.

      <Router primary={false}>
        <ScrollToTop path="/">
          <Home path="/" />
          <Contact path="contact-us" />
          <ThankYou path="thank-you" />
          <WhoWeAre path="who-we-are" />
        </ScrollToTop>
      </Router>

This is based off of React Router's scroll restoration guide.

The scroll to top component will still work with you don't have primary={false}, but it causes jank from where it focuses the route and then calls window.scrollTo.

// ScrollToTop.js
import React from 'react'

export const ScrollToTop = ({ children, location }) => {
  React.useEffect(() => window.scrollTo(0, 0), [location.pathname])
  return children
}

The top answer here, while solving the OP's problem, is probably not the solution most people want, since it turns off the most important accessibility feature of Reach router.

The fact Reach router focuses the content of the matched <Route> on a route change is for accessibility reasons - so screen readers etc can be directed to the newly updated, relevant content, when you navigate to a new page.

It uses HTMLElement.focus() to do this - see the MDN docs here.

The problem is that by default, this function scrolls to the element being focused. There is a preventScroll argument which can be used to turn this behaviour off, but the browser support for it is not good, and regardless, Reach Router does not use it.

Setting primary={false} turns this behaviour off for any nested <Router> you may have - it is not intended to set false on your main (primary) <Router> -- hence the name.

So, setting primary={false} on your primary <Router>, as the top answer suggests, 'works' in the sense that it stops the scrolling behaviour, but it achieves this by simply turning off the focusing behaviour completely, which breaks the accessibility feature. As I said, if you do this, you're breaking one of the main reasons to use Reach Router in the first place.

So, what's the solution?

Basically, it seems that this side effect of HTMLElement.focus() - scrolling to the focused element - is unavoidable. So if you want the accessibility feature, you have to take the scrolling behaviour with it.

But with that said, there might be a workaround. If you manually scroll to the top of the page using window.scrollTo(0, 0) on every route change, I believe that will not 'break' the focusing feature from an accessibility perspective, but will 'fix' the scrolling behaviour from a UX perspective.

Of course, it's a bit of a hacky and imperative workaround, but I think it's the best (maybe only) solution to this issue without breaking accessibility.

Here's how I implemented it

class OnRouteChangeWorker extends React.Component {
  componentDidUpdate(prevProps) {
    if (this.props.location.pathname !== prevProps.location.pathname) {
      this.props.action()
    }
  }

  render() {
    return null
  }
}

const OnRouteChange = ({ action }) => (
  {/* 
      Location is an import from @reach/router, 
      provides current location from context 
  */}
  <Location>
    {({ location }) => <OnRouteChangeWorker location={location} action={action} />}
  </Location>
)

const Routes = () => (
  <>
    <Router>
      <LayoutWithHeaderBar path="/">
        <Home path="/" />
        <Foo path="/foo" />
        <Bar path="/bar" />
      </LayoutWithHeaderBar>
    </Router>

    {/* 
        must come *after* <Router> else Reach router will call focus() 
        on the matched route after action is called, undoing the behaviour!
    */}
    <OnRouteChange action={() => { window.scrollTo(0, 0) } />
  </>
)