[docs] remove references to route fallthrough

documentation/docs/01-routing.md

@@ -92,8 +92,6 @@ The job of a [request handler](/docs/types#sveltejs-kit-requesthandler) is to re
 - `4xx` — client error
 - `5xx` — server error
 
-> If `{fallthrough: true}` is returned SvelteKit will [fall through](/docs/routing#advanced-routing-fallthrough-routes) to other routes until something responds, or will respond with a generic 404.
-
 #### Page endpoints
 
 If an endpoint has the same filename as a page (except for the extension), the page gets its props from the endpoint — via `fetch` during client-side navigation, or via direct function call during SSR.

documentation/docs/03-loading.md

@@ -30,8 +30,6 @@ As with [endpoints](/docs/routing#endpoints), pages can import [generated types]
 
 `load` is similar to `getStaticProps` or `getServerSideProps` in Next.js, except that `load` runs on both the server and the client. In the example above, if a user clicks on a link to this page the data will be fetched from `cms.example.com` without going via our server.
 
-If `load` returns `{fallthrough: true}`, SvelteKit will [fall through](/docs/routing#advanced-routing-fallthrough-routes) to other routes until something responds, or will respond with a generic 404.
-
 SvelteKit's `load` receives an implementation of `fetch`, which has the following special properties:
 
 - it has access to cookies on the server

documentation/docs/80-migrating.md

@@ -113,7 +113,7 @@ You access them differently in SvelteKit. `stores` is now `getStores`, but in mo
 
 #### Routing
 
-Regex routes are no longer supported. Instead, use [fallthrough routes](/docs/routing#advanced-routing-fallthrough-routes).
+Regex routes are no longer supported. Instead, use [advanced route matching](/docs/routing#advanced-routing-matching).
 
 #### URLs