1 files changed, 103 insertions, 36 deletions

diff --git a/doc/user/discussions/index.md b/doc/user/discussions/index.md
index bf3e907bd24..9320dbba1b8 100644
--- a/doc/user/discussions/index.md
+++ b/doc/user/discussions/index.md
@@ -5,14 +5,14 @@ info: "To determine the technical writer assigned to the Stage/Group associated
 type: reference, howto
 ---
 
-# Threads
+# Threads **(FREE)**
 
-The ability to contribute conversationally is offered throughout GitLab.
+GitLab encourages communication through comments, threads, and suggestions.
 
-You can leave a comment in the following places:
+For example, you can create a comment in the following places:
 
 - Issues
-- Epics **(ULTIMATE)**
+- Epics
 - Merge requests
 - Snippets
 - Commits
@@ -44,7 +44,7 @@ Thread resolution helps keep track of progress during planning or code review.
 Every standard comment or thread in merge requests, commits, commit diffs, and
 snippets is initially displayed as unresolved. They can then be individually resolved by anyone
 with at least Developer access to the project or by the author of the change being reviewed.
-If the thread has been resolved and a non-member unresolves their own response,
+If the thread has been resolved and a non-member un-resolves their own response,
 this will also unresolve the discussion thread.
 If the non-member then resolves this same response, this will resolve the discussion thread.
 
@@ -115,7 +115,7 @@ are resolved](#only-allow-merge-requests-to-be-merged-if-all-threads-are-resolve
 there will be an **open an issue to resolve them later** link in the merge
 request widget.
 
-![Link in merge request widget](img/resolve_thread_open_issue.png)
+![Link in merge request widget](img/resolve_thread_open_issue_v13_9.png)
 
 This will prepare an issue with its content referring to the merge request and
 the unresolved threads.
@@ -161,7 +161,7 @@ box and hit **Save** for the changes to take effect.
 From now on, you will not be able to merge from the UI until all threads
 are resolved.
 
-![Only allow merge if all the threads are resolved message](img/resolve_thread_open_issue.png)
+![Only allow merge if all the threads are resolved message](img/resolve_thread_open_issue_v13_9.png)
 
 ### Automatically resolve merge request diff threads when they become outdated
 
@@ -281,10 +281,27 @@ edit existing comments. Non-team members are restricted from adding or editing c
 
 Additionally, locked issues and merge requests can not be reopened.
 
+## Confidential Comments
+
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/207473) in GitLab 13.9.
+> - It's [deployed behind a feature flag](../feature_flags.md), disabled by default.
+> - It's disabled on GitLab.com.
+> - It's not recommended for production use.
+> - To use it in GitLab self-managed instances, ask a GitLab administrator to enable it. **(FREE SELF)**
+
+WARNING:
+This feature might not be available to you. Check the **version history** note above for details.
+
+When creating a comment, you can decide to make it visible only to the project members (users with Reporter and higher permissions).
+
+To create a confidential comment, select the **Make this comment confidential** checkbox before you submit it.
+
+![Confidential comments](img/confidential_comments_v13_9.png)
+
 ## Merge Request Reviews
 
 > - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/4213) in [GitLab Premium](https://about.gitlab.com/pricing/) 11.4.
-> - [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/28154) to GitLab Core in 13.1.
+> - [Moved](https://gitlab.com/gitlab-org/gitlab/-/issues/28154) to GitLab Free in 13.1.
 
 When looking at a Merge Request diff, you are able to start a review.
 This allows you to create comments inside a Merge Request that are **only visible to you** until published,
@@ -370,13 +387,18 @@ From a merge request's **Discussion** tab, or from an epic/issue overview, find
 
 ![Notes filters dropdown options](img/index_notes_filters.png)
 
-Once you select one of the filters in a given issue or MR, GitLab will save
+After you select one of the filters in a given issue or MR, GitLab will save
 your preference, so that it will persist when you visit the same page again
 from any device you're logged into.
 
 ## Suggest Changes
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/18008) in GitLab 11.6.
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/18008) in GitLab 11.6.
+> - Custom commit messages for suggestions was [introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/25381) in GitLab 13.9.
+> - Custom commit messages for suggestions was deployed behind a [feature flag](../feature_flags.md), disabled by default.
+> - Custom commit messages for suggestions became enabled by default on GitLab 13.9.
+> - Custom commit messages for suggestions is enabled on GitLab.com and is recommended for production use.
+> - For GitLab self-managed instances, GitLab administrators can opt to [disabled it](#enable-or-disable-custom-commit-messages-for-suggestions). **(FREE SELF)**
 
 As a reviewer, you're able to suggest code changes with a simple
 Markdown syntax in Merge Request Diff threads. Then, the
@@ -388,20 +410,27 @@ the merge request authored by the user that applied them.
 1. Choose a line of code to be changed, add a new comment, then click
    on the **Insert suggestion** icon in the toolbar:
 
-   ![Add a new comment](img/suggestion_button_v12_7.png)
+   ![Add a new comment](img/suggestion_button_v13_9.png)
 
 1. In the comment, add your suggestion to the pre-populated code block:
 
-   ![Add a suggestion into a code block tagged properly](img/make_suggestion_v12_7.png)
+   ![Add a suggestion into a code block tagged properly](img/make_suggestion_v13_9.png)
 
 1. Click either **Start a review** or **Add to review** to add your comment to a [review](#merge-request-reviews), or **Add comment now** to add the comment to the thread immediately.
 
    The Suggestion in the comment can be applied by the merge request author
    directly from the merge request:
 
-   ![Apply suggestions](img/apply_suggestion_v12_7.png)
+   ![Apply suggestions](img/apply_suggestion_v13_9.png)
+
+1. [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/25381) in GitLab 13.9,
+   you can opt to add a custom commit message to describe your change. If you don't
+   specify it, the default commit message will be used. Note that [this feature may not be available to you](#enable-or-disable-custom-commit-messages-for-suggestions).
+   Also, it is not supported for [batch suggestions](#batch-suggestions).
 
-Once the author applies a Suggestion, it will be marked with the **Applied** label,
+   ![Custom commit](img/custom_commit_v13_9.png)
+
+After the author applies a Suggestion, it will be marked with the **Applied** label,
 the thread will be automatically resolved, and GitLab will create a new commit
 and push the suggested change directly into the codebase in the merge request's
 branch. [Developer permission](../permissions.md) is required to do so.
@@ -501,27 +530,6 @@ to your branch to address your reviewers' requests.
 
    ![A code change suggestion displayed, with the button to apply the batch of suggestions highlighted.](img/apply_batch_of_suggestions_v13_1.jpg "Apply a batch of suggestions")
 
-#### Enable or disable Batch Suggestions **(CORE ONLY)**
-
-Batch Suggestions is
-deployed behind a feature flag that is **enabled by default**.
-[GitLab administrators with access to the GitLab Rails console](../../administration/feature_flags.md)
-can opt to disable it for your instance.
-
-To enable it:
-
-```ruby
-# Instance-wide
-Feature.enable(:batch_suggestions)
-```
-
-To disable it:
-
-```ruby
-# Instance-wide
-Feature.disable(:batch_suggestions)
-```
-
 ## Start a thread by replying to a standard comment
 
 > [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/30299) in GitLab 11.9
@@ -537,7 +545,7 @@ Clicking on the **Reply to comment** button will bring the reply area into focus
 ![Reply to comment feature](img/reply_to_comment.gif)
 
 Replying to a non-thread comment will convert the non-thread comment to a
-thread once the reply is submitted. This conversion is considered an edit
+thread after the reply is submitted. This conversion is considered an edit
 to the original comment, so a note about when it was last edited will appear underneath it.
 
 This feature only exists for Issues, Merge requests, and Epics. Commits, Snippets and Merge request diff threads are
@@ -554,3 +562,62 @@ In the comment, click the **More Actions** menu and click **Assign to commenting
 Click the button again to unassign the commenter.
 
 ![Assign to commenting user](img/quickly_assign_commenter_v13_1.png)
+
+## Enable or disable Confidential Comments **(FREE SELF)**
+
+Confidential Comments is under development and not ready for production use. It is
+deployed behind a feature flag that is **disabled by default**.
+[GitLab administrators with access to the GitLab Rails console](../../administration/feature_flags.md)
+can enable it.
+
+To enable it:
+
+```ruby
+Feature.enable(:confidential_notes)
+```
+
+To disable it:
+
+```ruby
+Feature.disable(:confidential_notes)
+```
+
+## Enable or disable Custom commit messages for suggestions **(FREE SELF)**
+
+Custom commit messages for suggestions is under development but ready for production use. It is
+deployed behind a feature flag that is **enabled by default**.
+[GitLab administrators with access to the GitLab Rails console](../../administration/feature_flags.md)
+can opt to disable it.
+
+To disable custom commit messages for suggestions:
+
+```ruby
+Feature.disable(:suggestions_custom_commit)
+```
+
+To enable custom commit messages for suggestions:
+
+```ruby
+Feature.enable(:suggestions_custom_commit)
+```
+
+## Enable or disable Batch Suggestions **(FREE SELF)**
+
+Batch Suggestions is
+deployed behind a feature flag that is **enabled by default**.
+[GitLab administrators with access to the GitLab Rails console](../../administration/feature_flags.md)
+can opt to disable it for your instance.
+
+To enable it:
+
+```ruby
+# Instance-wide
+Feature.enable(:batch_suggestions)
+```
+
+To disable it:
+
+```ruby
+# Instance-wide
+Feature.disable(:batch_suggestions)
+```