Issue when rendering server side with react (checksum warning)

[swernerx]

It seems like NavLink is behaving differently on client and server.

I have this code in my application:

import { Switch, Route, NavLink } from "react-router-dom"

...

<ul>
  <li><NavLink to="/" activeClassName={Styles.activeLink}>Home</NavLink></li>
  <li><NavLink to="/about" activeClassName={Styles.activeLink}>About</NavLink></li>
</ul>

In the markup this seems to produce double slashes for href:

<ul data-reactid="7">
<li data-reactid="8"><a class="src-app-AppContainer-activeLink " href="//" data-reactid="9">Home</a></li>
<li data-reactid="10"><a href="//about" data-reactid="11">About</a></li>
</ul>

That's the warning I am seeing in the client:

warning.js:36 Warning: React attempted to reuse markup in a container but the checksum was invalid. This generally means that you are using server rendering and the markup generated on the server was not what the client was expecting. React injected new markup to compensate which works but you have lost many of the benefits of server rendering. Instead, figure out why the markup being generated is different on the client or server:
 (client) activeLink " href="/" data-reactid="9">H
 (server) activeLink " href="//" data-reactid="9">

[pshrmn]

Fixed in #4484

[swernerx]

Ah perfect 👍