> For the complete documentation index, see [llms.txt](https://medusa-ui.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://medusa-ui.gitbook.io/docs/medusa/inner-workings.md).

# Inner workings

What path does a request take through Medusa?

1. Browser call
2. `RequestStreamHandler` or `RequestStreamHandlerWithSecurity`\
   *depending on if the `ReactiveSecurityContextHolder` bean is available*
3. `HTMLInjector.inject`
4. ...

**Troubleshooting**

*Blank page when calling a page*

This means that somewhere in the reactive chain something didn't resolve. For example, the Reactive security context did not load. So the chain to inject HTML gets broken, and resolves without giving you HTML (=shows you a blank page)

If the situation where the chain is broken is actually correct, then a `switchIfEmpty()` needs to be implemented and a default value provided.