How to implement _default_ or _NotFound_ page?

A <Switch> renders the first child <Route> that matches. A <Route> with no path always matches. So you just need to simply drop path attribute as below

<Switch>
<Route exact path="/" component={Home} />
<Route path="/user" component={User} />
<Route component={NotFound} />
</Switch>

September 26, 2022
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