I've been struggling for the last few days to eliminate page flash. My project started with create-react-app, then I used help to set up SSR and various other options. When I started running into problems, I stripped my code down and ejected. Here is my code. You can build with npm run build and start the SSR with npm run serve. Visit http://localhost:3000/ to see the result.
There are two routes in my app: Home and About.
Going to / (Home) works as desired: react-loadable identifies the home bundle, injects a <script> tag for it, and sends the page out the door. The client loads all the bundles and react takes over with no flash.
Going to /about results in a page flash (make sure the page is loaded from the server to see this). I added an import for moment-timezone into the about component, and webpack smartly moves it into its own bundle, separate from the about bundle. The problem is that react-loadable only sees that it needs the about bundle, not the extra bundle containing moment-timezone. Thus, on the client side, when react takes over it sees that its missing a module, blanks the page, loads the bundle containing the missing module, then re-renders (at least,
I think that's how it works).
What am I missing? I am using the babel and webpack plugins as described in the React-Loadable Readme. It seems like React-Loadable is only smart enough to go one level deep and not see what the imported module's dependencies are, but surely that's not the case, is it?
This happens because react-loadable don't have a nice and deep implementation for server side rendering.
But the good news is, there's an add-on for that, it is called react-loadable-ssr-addon.
In the plugin repository it says:
React Loadable SSR Add-on is a server side render add-on for React Loadable that helps you to load dynamically all files dependencies, e.g. splitted chunks, css, etc.
Oh yeah, and we also provide support for SRI (Subresource Integrity).
So basically this plugin handle everything regarding the assets situation for server side rendering in react, reproducing the same behaviour as the tradicional approach (client side render).
With that, your assets are managed and loaded automatically to your output, avoiding the error you reported.