Edited for style and CTRT

Related to: https://gitlab.com/gitlab-org/gitlab/-/issues/300312

doc/administration/instance_limits.md

@@ -149,7 +149,7 @@ limited to 1KiB, and descriptions (the rest of the message) will be limited to
 
 The maximum number of issues loaded on the milestone overview page is 3000.
 When the number exceeds the limit the page displays an alert and links to a paginated
-[issue list](../user/project/issues/index.md#issues-list) of all issues in the milestone.
+[issue list](../user/project/issues/managing_issues.md) of all issues in the milestone.
 
 - **Limit:** 3000 issues
 

doc/user/group/bulk_editing/index.md

@@ -31,7 +31,7 @@ When bulk editing issues in a group, you can edit the following attributes:
 - [Epic](../epics/index.md)
 - [Milestone](../../project/milestones/index.md)
 - [Labels](../../project/labels.md)
-- [Health status](../../project/issues/index.md#health-status)
+- [Health status](../../project/issues/managing_issues.md#health-status)
 - [Iteration](../iterations/index.md)
 
 To update multiple project issues at the same time:

doc/user/group/epics/index.md

@@ -81,7 +81,7 @@ to:
 > - The health status of a closed issue [is hidden](https://gitlab.com/gitlab-org/gitlab/-/issues/220867) in [GitLab Ultimate](https://about.gitlab.com/pricing/) 13.3 or later.
 > - [Feature flag removed](https://gitlab.com/gitlab-org/gitlab/-/issues/213567) in GitLab 13.7.
 
-Report or respond to the health of issues and epics by setting a red, amber, or green [health status](../../project/issues/index.md#health-status), which then appears on your Epic tree.
+Report or respond to the health of issues and epics by setting a red, amber, or green [health status](../../project/issues/managing_issues.md#health-status), which then appears on your Epic tree.
 
 ## Multi-level child epics **(ULTIMATE)**
 

doc/user/group/index.md

@@ -16,7 +16,7 @@ Then you can:
 
 - Grant members access to multiple projects at once.
 - Add to-do items for all of the group members at once.
-- View the [issues](../project/issues/index.md#issues-list) and
+- View the [issues](../project/issues/index.md) and
   [merge requests](../project/merge_requests/reviewing_and_managing_merge_requests.md#view-merge-requests-for-all-projects-in-a-group)
   for all projects in the group, together in a single list view.
 - [Bulk edit](../group/bulk_editing/index.md) issues, epics, and merge requests.

doc/user/index.md

@@ -42,7 +42,7 @@ GitLab is a Git-based platform that integrates a great number of essential tools
 
 - Hosting code in repositories with version control.
 - Tracking proposals for new implementations, bug reports, and feedback with a
-  fully featured [Issue Tracker](project/issues/index.md#issues-list).
+  fully featured [Issue tracker](project/issues/index.md).
 - Organizing and prioritizing with [Issue Boards](project/issue_board.md).
 - Reviewing code in [Merge Requests](project/merge_requests/index.md) with live-preview changes per
   branch with [Review Apps](../ci/review_apps/index.md).

doc/user/project/bulk_editing.md

@@ -33,7 +33,7 @@ When bulk editing issues in a project, you can edit the following attributes:
 - [Epic](../group/epics/index.md)
 - [Milestone](milestones/index.md)
 - [Labels](labels.md)
-- [Health status](issues/index.md#health-status)
+- [Health status](issues/managing_issues.md#health-status)
 - Notification subscription
 - [Iteration](../group/iterations/index.md)
 

doc/user/project/issue_board.md

@@ -14,7 +14,7 @@ It can be used as a [Kanban](https://en.wikipedia.org/wiki/Kanban_(development))
 It pairs issue tracking and project management, keeping everything together,
 so that you don't need to jump between different platforms to organize your workflow.
 
-Issue boards build on the existing [issue tracking functionality](issues/index.md#issues-list) and
+Issue boards build on the existing [issue tracking functionality](issues/index.md) and
 [labels](labels.md). Your issues appear as cards in vertical lists, organized by their assigned
 labels, [milestones](#milestone-lists), or [assignees](#assignee-lists).
 
@@ -88,7 +88,7 @@ You can tailor GitLab issue boards to your own preferred workflow.
 Here are some common use cases for issue boards.
 
 For examples of using issue boards along with [epics](../group/epics/index.md),
-[issue health status](issues/index.md#health-status), and
+[issue health status](issues/managing_issues.md#health-status), and
 [scoped labels](labels.md#scoped-labels) for various Agile frameworks, check:
 
 - The [How to use GitLab for Agile portfolio planning and project management](https://about.gitlab.com/blog/2020/11/11/gitlab-for-agile-portfolio-planning-project-management/) blog post (November 2020)

doc/user/project/issues/due_dates.md

@@ -37,7 +37,7 @@ The last way to set a due date is by using [quick actions](../quick_actions.md),
 
 ## Making use of due dates
 
-You can see issues with their due dates in the [issues list](index.md#issues-list).
+You can see issues with their due dates in the issues list.
 Overdue issues have their icon and date colored red.
 To sort issues by their due dates, select **Due date** from the dropdown menu on the right.
 Issues are then sorted from the earliest due date to the latest.

doc/user/project/issues/managing_issues.md

@@ -144,7 +144,7 @@ Follow these examples to form your new issue URL with prefilled fields.
 - For a new issue in the GitLab Community Edition project with a pre-filled title,
   a pre-filled description, and the confidential flag set, the URL would be `https://gitlab.com/gitlab-org/gitlab-foss/-/issues/new?issue[title]=Validate%20new%20concept&issue[description]=Research%20idea&issue[confidential]=true`
 
-## Moving Issues
+## Moving issues
 
 Moving an issue copies it to the target project, and closes it in the originating project.
 The original issue is not deleted. A system note, which indicates
@@ -154,7 +154,7 @@ The "Move issue" button is at the bottom of the right-sidebar when viewing the i
 
 ![move issue - button](img/sidebar_move_issue.png)
 
-### Moving Issues in Bulk
+### Moving issues in bulk **(FREE SELF)**
 
 If you have advanced technical skills you can also bulk move all the issues from
 one project to another in the rails console. The below script moves all issues
@@ -315,3 +315,79 @@ To add an issue to an [iteration](../../group/iterations/index.md):
 You can also use the `/iteration`
 [quick action](../quick_actions.md#issues-merge-requests-and-epics)
 in a comment or description field.
+
+## Real-time sidebar **(FREE SELF)**
+
+> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/17589) in GitLab 13.3.
+
+Assignees in the sidebar are updated in real time. This feature is **disabled by default**.
+To enable it, you need to enable [ActionCable in-app mode](https://docs.gitlab.com/omnibus/settings/actioncable.html).
+
+## Cached issue count **(FREE SELF)**
+
+> - [Introduced]([link-to-issue](https://gitlab.com/gitlab-org/gitlab/-/issues/243753)) 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 this feature in GitLab self-managed instances, ask a GitLab administrator to [enable it](#enable-or-disable-cached-issue-count) **(FREE SELF)**
+
+WARNING:
+This feature might not be available to you. Check the **version history** note above for details.
+
+In a group, the sidebar displays the total count of open issues and this value is cached if higher
+than 1000. The cached value is rounded to thousands (or millions) and updated every 24 hours.
+
+## Similar issues
+
+> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/22866) in GitLab 11.6.
+
+To prevent duplication of issues for the same topic, GitLab searches for similar issues
+when new issues are being created.
+
+As you type in the title field of the **New Issue** page, GitLab searches titles and descriptions
+across all issues to in the current project. Only issues you have access to are returned.
+Up to five similar issues, sorted by most recently updated, are displayed below the title box.
+[GraphQL](../../../api/graphql/index.md) must be enabled to use this feature.
+
+![Similar issues](img/similar_issues.png)
+
+## Health status **(ULTIMATE)**
+
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/36427) in GitLab Ultimate 12.10.
+> - Health status of closed issues [can't be edited](https://gitlab.com/gitlab-org/gitlab/-/issues/220867) in GitLab Ultimate 13.4 and later.
+> - Issue health status visible in issue lists [introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/45141) in GitLab Ultimate 13.6.
+> - [Feature flag removed](https://gitlab.com/gitlab-org/gitlab/-/issues/213567) in GitLab 13.7.
+
+To help you track issue statuses, you can assign a status to each issue.
+This marks issues as progressing as planned or needs attention to keep on schedule:
+
+- **On track** (green)
+- **Needs attention** (amber)
+- On track (green)
+- Needs attention (amber)
+- At risk (red)
+
+After an issue is closed, its health status can't be edited and the **Edit** button becomes disabled
+until the issue is reopened.
+
+You can then see issue statuses in the issues list and the
+[epic tree](../../group/epics/index.md#issue-health-status-in-epic-tree).
+
+## Enable or disable cached issue count **(FREE SELF)**
+
+Cached issue count in the left sidebar is under development and not 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 disable it.
+
+To disable it:
+
+```ruby
+Feature.disable(:cached_sidebar_open_issues_count)
+```
+
+To enable it:
+
+```ruby
+Feature.enable(:cached_sidebar_open_issues_count)
+```