[8.15] [BUG] All Kibana privileges don't grant Security / Elastic Defend features by default (backport #6134) (#6138)

* [BUG] All Kibana privileges don't grant Security / Elastic Defend features by default (#6134)

* Align with ESS on nav steps

* Add admonition for emphasis

(cherry picked from commit fb6875d)

# Conflicts:
#	docs/serverless/edr-install-config/defend-feature-privs.asciidoc

* Delete docs/serverless directory and its contents

---------

Co-authored-by: Joe Peeples <[email protected]>
Co-authored-by: github-actions[bot] <github-actions[bot]@users.noreply.github.com>

Author: 3 people

docs/getting-started/defend-feature-privs.asciidoc

@@ -15,7 +15,11 @@ NOTE: {elastic-defend}'s feature privileges must be assigned to *All Spaces*. Yo
 [role="screenshot"]
 image::images/endpoint-privileges.png[Configuring privileges in Kibana,75%]
 
-To grant access, select *All* for the *Security* feature in the *{kib} privileges* configuration UI, then turn on the *Customize sub-feature privileges* switch. For each of the following sub-feature privileges, select the type of access you want to allow:
+To grant access, select *All* for the *Security* feature in the *Assign role to space* configuration UI, then turn on the *Customize sub-feature privileges* switch. 
+
+IMPORTANT: Selecting **All** for the overall **Security** feature does NOT enable any sub-features. You must also enable the **Customize sub-feature privileges** switch, and then enable each sub-feature privilege individually.
+
+For each of the following sub-feature privileges, select the type of access you want to allow:
 
 * *All*: Users have full access to the feature, which includes performing all available actions and managing configuration.
 * *Read*: Users can view the feature, but can't perform any actions or manage configuration. (Some features don't have this privilege.)