[9.2] [DOCS][ResponseOps][Alerting][9.1]: Add breaking change to CCS-based reporting to 9.1 Kibana release notes (#245183) (#245276)

# Backport

This will backport the following commits from `main` to `9.2`:
- [[DOCS][ResponseOps][Alerting][9.1]: Add breaking change to CCS-based
reporting to 9.1 Kibana release notes
(#245183)](#245183)

<!--- Backport version: 9.6.6 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sorenlouv/backport)

<!--BACKPORT [{"author":{"name":"Nastasha
Solomon","email":"79124755+nastasha-solomon@users.noreply.github.com"},"sourceCommit":{"committedDate":"2025-12-04T16:49:32Z","message":"[DOCS][ResponseOps][Alerting][9.1]:
Add breaking change to CCS-based reporting to 9.1 Kibana release notes
(#245183)\n\n## Summary\n\nContributes
to\nhttp://github.com/elastic/docs-content-internal/issues/514
by\ndocumenting the breaking change to CCS-based reporting in the 9.1
Kibana\nrelease notes.\n\nAlso took this opportunity to remove the `%`
char from some breaking\nchange descriptions (it was commenting out
lines).\n\n### Corresponding fixes\n- 8.19 reporting docs and Kibana
release notes:\nhttps://github.com//pull/245182\n- 9.1
reporting docs: https://github.com/elastic/docs-content/pull/4211\n\n##
Previews\n\n-\n[9.1](https://docs-v3-preview.elastic.dev/elastic/kibana/pull/245183/release-notes/breaking-changes#kibana-9.1.0-breaking-changes)\n-
see the second item in the
section","sha":"a7a6130042f450e4ffcd560b8452bc9fdd7c43b4","branchLabelMapping":{"^v9.3.0$":"main","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["release_note:skip","docs","backport:version","v9.1.0","v9.2.0","v9.3.0"],"title":"[DOCS][ResponseOps][Alerting][9.1]:
Add breaking change to CCS-based reporting to 9.1 Kibana release
notes","number":245183,"url":"https://github.com/elastic/kibana/pull/245183","mergeCommit":{"message":"[DOCS][ResponseOps][Alerting][9.1]:
Add breaking change to CCS-based reporting to 9.1 Kibana release notes
(#245183)\n\n## Summary\n\nContributes
to\nhttp://github.com/elastic/docs-content-internal/issues/514
by\ndocumenting the breaking change to CCS-based reporting in the 9.1
Kibana\nrelease notes.\n\nAlso took this opportunity to remove the `%`
char from some breaking\nchange descriptions (it was commenting out
lines).\n\n### Corresponding fixes\n- 8.19 reporting docs and Kibana
release notes:\nhttps://github.com//pull/245182\n- 9.1
reporting docs: https://github.com/elastic/docs-content/pull/4211\n\n##
Previews\n\n-\n[9.1](https://docs-v3-preview.elastic.dev/elastic/kibana/pull/245183/release-notes/breaking-changes#kibana-9.1.0-breaking-changes)\n-
see the second item in the
section","sha":"a7a6130042f450e4ffcd560b8452bc9fdd7c43b4"}},"sourceBranch":"main","suggestedTargetBranches":["9.1","9.2"],"targetPullRequestStates":[{"branch":"9.1","label":"v9.1.0","branchLabelMappingKey":"^v(\\d+).(\\d+).\\d+$","isSourceBranch":false,"state":"NOT_CREATED"},{"branch":"9.2","label":"v9.2.0","branchLabelMappingKey":"^v(\\d+).(\\d+).\\d+$","isSourceBranch":false,"state":"NOT_CREATED"},{"branch":"main","label":"v9.3.0","branchLabelMappingKey":"^v9.3.0$","isSourceBranch":true,"state":"MERGED","url":"https://github.com/elastic/kibana/pull/245183","number":245183,"mergeCommit":{"message":"[DOCS][ResponseOps][Alerting][9.1]:
Add breaking change to CCS-based reporting to 9.1 Kibana release notes
(#245183)\n\n## Summary\n\nContributes
to\nhttp://github.com/elastic/docs-content-internal/issues/514
by\ndocumenting the breaking change to CCS-based reporting in the 9.1
Kibana\nrelease notes.\n\nAlso took this opportunity to remove the `%`
char from some breaking\nchange descriptions (it was commenting out
lines).\n\n### Corresponding fixes\n- 8.19 reporting docs and Kibana
release notes:\nhttps://github.com//pull/245182\n- 9.1
reporting docs: https://github.com/elastic/docs-content/pull/4211\n\n##
Previews\n\n-\n[9.1](https://docs-v3-preview.elastic.dev/elastic/kibana/pull/245183/release-notes/breaking-changes#kibana-9.1.0-breaking-changes)\n-
see the second item in the
section","sha":"a7a6130042f450e4ffcd560b8452bc9fdd7c43b4"}}]}]
BACKPORT-->

Co-authored-by: Nastasha Solomon <79124755+nastasha-solomon@users.noreply.github.com>

Author: kibanamachine

docs/release-notes/breaking-changes.md

@@ -39,19 +39,30 @@ If you are migrating from a version prior to version 9.0, you must first upgrade
 ## 9.2.0 [kibana-9.2.0-breaking-changes]
 $$$kibana-230067$$$
 ::::{dropdown} Improved advanced settings management APIs privilege checks 
-% **Details**<br> Roles with explicit `read` access to advanced settings but `all` access to `SavedObjectManagement` can no longer update settings using the internal advanced settings API. This update enforces explicit privileges instead of relying on saved object security checks.
+**Details**<br> Roles with explicit `read` access to advanced settings but `all` access to `SavedObjectManagement` can no longer update settings using the internal advanced settings API. This update enforces explicit privileges instead of relying on saved object security checks.
 View [#230067]({{kib-pull}}230067).
 ::::
 
 ## 9.1.0 [kibana-9.1.0-breaking-changes]
 $$$kibana-213916$$$
 ::::{dropdown} Change to variable syntax in {{esql}} queries
 
-% **Details**<br> Fields and functions variables are now described with `??` in {{esql}} queries. For value variables, you can continue to use `?`. 
+**Details**<br> Fields and functions variables are now described with `??` in {{esql}} queries. For value variables, you can continue to use `?`. 
 
 View [#213916]({{kib-pull}}213916).
 ::::
 
+$$$kibana-216558$$$
+::::{dropdown} API keys are used for authenticating report generation requests
+
+**Details**<br> In 9.1.0, report generation requests are authenticated by API keys instead of session cookies. There are several key differences between the authentication methods. API keys capture your role privileges, whereas session cookie are based on your user credentials. API keys are also longer-lived, compared to session cookies, which have a shorter lifespan.
+
+
+If you have a cross-cluster search environment and want to generate reports from remote clusters, you must have the appropriate cluster and index privileges on the remote cluster and local cluster. For example, if requests are authenticated with an API key, the API key requires certain privileges on the local cluster that contains the local index, in addition to the remote. For more information and examples, refer to [Configure roles and users for remote clusters](docs-content://deploy-manage/remote-clusters/remote-clusters-cert.md#remote-clusters-privileges-cert).
+
+View [#216558]({{kib-pull}}216558).
+::::
+
 ## 9.0.0 [kibana-900-breaking-changes]
 $$$kibana-193792$$$
 :::{dropdown} Access to {{kib}}'s internal APIs is blocked