Add links to WebFlux section where referenced

Closes gh-14100

docs/modules/ROOT/pages/features/authentication/index.adoc

@@ -8,4 +8,4 @@ Once authentication is performed we know the identity and can perform authorizat
 
 Spring Security provides built in support for authenticating users.
 This section is dedicated to generic authentication support that applies in both Servlet and WebFlux environments.
-Refer to the sections on authentication for xref:servlet/authentication/index.adoc#servlet-authentication[Servlet] and WebFlux for details on what is supported for each stack.
+Refer to the sections on authentication for xref:servlet/authentication/index.adoc#servlet-authentication[Servlet] and xref:servlet/authentication/index.adoc[WebFlux] for details on what is supported for each stack.

docs/modules/ROOT/pages/features/authorization/index.adoc

@@ -8,7 +8,9 @@ Spring Security provides https://en.wikipedia.org/wiki/Defense_in_depth_(computi
 [[authorization-request]]
 == Request Based Authorization
 
-Spring Security provides authorization based upon the request for both xref:servlet/authorization/index.adoc[Servlet] and WebFlux environments.
+Spring Security provides authorization based upon the request for both xref:servlet/authorization/authorize-http-requests.adoc[Servlet] and xref:reactive/authorization/authorize-http-requests.adoc[WebFlux] environments.
 
 [[authorization-method]]
 == Method Based Authorization
+
+Spring Security provides authorization based on the method invocation for both xref:servlet/authorization/method-security.adoc[Servlet] and xref:reactive/authorization/method.adoc[WebFlux] environments.

docs/modules/ROOT/pages/features/integrations/index.adoc

@@ -4,5 +4,4 @@
 
 Spring Security provides integrations with numerous frameworks and APIs.
 In this section, we discuss generic integrations that are not specific to Servlet or Reactive environments.
-To see specific integrations, refer to the xref:servlet/integrations/index.adoc[Servlet] and xref:servlet/integrations/index.adoc[Reactive] Integrations sections.
-// FIXME add link to reactive integrations
+To see specific integrations, refer to the xref:servlet/integrations/index.adoc[Servlet] and xref:reactive/integrations/cors.adoc[Reactive] Integrations sections.