[Docs] Update related issues doc move to core

doc/README.md

@@ -121,7 +121,7 @@ The following documentation relates to the DevOps **Plan** stage:
 | [Milestones](user/project/milestones/index.md)                                                                                                                                                                                                                     | Set milestones for delivery of issues and merge requests, with optional due date.                                                                |
 | [Project Issue Board](user/project/issue_board.md)                                                                                                                                                                                                                 | Display issues on a Scrum or Kanban board.                                                                                                       |
 | [Quick Actions](user/project/quick_actions.md)                                                                                                                                                                                                                     | Shortcuts for common actions on issues or merge requests, replacing the need to click buttons or use dropdowns in GitLab's UI.                   |
-| [Related Issues](user/project/issues/related_issues.md) **(STARTER)**                                                                                                                                                                                              | Create a relationship between issues.                                                                                                            |
+| [Related Issues](user/project/issues/related_issues.md)                                                                                                                                                                                                          | Create a relationship between issues.                                                                                                            |
 | [Requirements Management](user/project/requirements/index.md) **(ULTIMATE)** | Check your products against a set of criteria. |
 | [Roadmap](user/group/roadmap/index.md) **(ULTIMATE)**                                                                                                                                                                                                              | Visualize epic timelines.                                                                                                                        |
 | [Service Desk](user/project/service_desk.md)                                                                                                                                                                                                         | A simple way to allow people to create issues in your GitLab instance without needing their own user account.                                    |

doc/api/issue_links.md

-# Issue links API **(STARTER)**
+# Issue links API **(CORE)**
+
+> The simple "relates to" relationship [moved](https://gitlab.com/gitlab-org/gitlab/-/issues/212329) to [GitLab Core](https://about.gitlab.com/pricing/) in 13.4.
 
 ## List issue relations
 
-Get a list of related issues of a given issue, sorted by the relationship creation datetime (ascending).
+Get a list of a given issue's [related issues](../user/project/issues/related_issues.md),
+sorted by the relationship creation datetime (ascending).
 Issues will be filtered according to the user authorizations.
 
 ```plaintext

doc/user/permissions.md

@@ -72,7 +72,7 @@ The following table depicts the various user permission levels in a project.
 | Set issue weight                                  |         | ✓          | ✓           | ✓        | ✓      |
 | Lock issue threads                                |         | ✓          | ✓           | ✓        | ✓      |
 | Manage issue tracker                              |         | ✓          | ✓           | ✓        | ✓      |
-| Manage related issues **(STARTER)**               |         | ✓          | ✓           | ✓        | ✓      |
+| Manage related issues                             |         | ✓          | ✓           | ✓        | ✓      |
 | Manage labels                                     |         | ✓          | ✓           | ✓        | ✓      |
 | Create code snippets                              |         | ✓          | ✓           | ✓        | ✓      |
 | See a commit status                               |         | ✓          | ✓           | ✓        | ✓      |
@@ -284,7 +284,7 @@ group.
    - The [instance level](admin_area/settings/visibility_and_access_controls.md#default-project-creation-protection).
    - The [group level](group/index.md#default-project-creation-level).
 1. Does not apply to subgroups.
-1. Developers can push commits to the default branch of a new project only if the [default branch protection](group/index.md#changing-the-default-branch-protection-of-a-group) is set to "Partially protected" or "Not protected". 
+1. Developers can push commits to the default branch of a new project only if the [default branch protection](group/index.md#changing-the-default-branch-protection-of-a-group) is set to "Partially protected" or "Not protected".
 
 ### Subgroup permissions
 

doc/user/project/issues/index.md

@@ -156,12 +156,15 @@ collaborate with your team.
 efficiently and with less effort by tracking groups of issues that share a theme, across
 projects and milestones.
 
-### Related issues **(STARTER)**
+### Related issues
 
 You can mark two issues as related, so that when viewing one, the other is always
 listed in its [Related Issues](related_issues.md) section. This can help display important
 context, such as past work, dependencies, or duplicates.
 
+Users on [GitLab Starter, GitLab Bronze, and higher tiers](https://about.gitlab.com/pricing/), can
+also mark issues as blocking or blocked by another issue.
+
 ### Crosslinking issues
 
 You can [cross-link issues](crosslinking_issues.md) by referencing an issue from another

doc/user/project/issues/issue_data_and_actions.md

@@ -36,7 +36,7 @@ You can find all the information for that issue on one screen.
 - **15.** [Edit](#edit)
 - **16.** [Description](#description)
 - **17.** [Mentions](#mentions)
-- **18.** [Related Issues **(STARTER)**](#related-issues)
+- **18.** [Related Issues](#related-issues)
 - **19.** [Related Merge Requests](#related-merge-requests)
 - **20.** [Award emoji](#award-emoji)
 - **21.** [Show all activity](#show-all-activity)
@@ -208,7 +208,7 @@ TIP: **Tip:**
 Avoid mentioning `@all` in issues and merge requests, as it sends an email notification
 to all the members of that project's group, which can be interpreted as spam.
 
-### Related Issues **(STARTER)**
+### Related Issues
 
 Issues that were mentioned as [related issues](related_issues.md) are listed here.
 You can also click the `+` to add more related issues.

doc/user/project/issues/related_issues.md

@@ -4,33 +4,40 @@ group: Project Management
 info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#designated-technical-writers
 ---
 
-# Related issues **(STARTER)**
+# Related issues **(CORE)**
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/1797) in [GitLab Starter](https://about.gitlab.com/pricing/) 9.4.
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/1797) in [GitLab Starter](https://about.gitlab.com/pricing/) 9.4.
+> - The simple "relates to" relationship [moved](https://gitlab.com/gitlab-org/gitlab/-/issues/212329) to [GitLab Core](https://about.gitlab.com/pricing/) in 13.4.
 
 Related issues are a bi-directional relationship between any two issues
 and appear in a block below the issue description. Issues can be across groups
 and projects.
 
+You can set any issue as:
+
+- Related to another issue
+- Blocking another issue **(STARTER)**
+- Blocked by another issue **(STARTER)**
+
 The relationship only shows up in the UI if the user can see both issues.
 
 When you try to close an issue that has open blockers, a warning is displayed.
 
 TIP: **Tip:**
-To manage related issues through our API, see the [API documentation](../../../api/issue_links.md).
+To manage related issues through our API, visit the [issue links API documentation](../../../api/issue_links.md).
 
 ## Adding a related issue
 
 > - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/2035) in [GitLab Starter](https://about.gitlab.com/pricing/) 12.8.
 > - [Improved](https://gitlab.com/gitlab-org/gitlab/-/issues/34239) to warn when attempting to close an issue that is blocked by others in [GitLab Starter](https://about.gitlab.com/pricing/) 13.0.
->   When you try to close an issue with open blockers, you'll see a warning that you can dismiss.
+>   When you try to close an issue with open blockers, you see a warning that you can dismiss.
 
 1. Relate one issue to another by clicking the related issues "+" button
 in the header of the related issue block.
 
 1. Input the issue reference number or paste in the full URL of the issue.
 
-1. Select whether the current issue relates to, blocks, or is blocked by the issues being entered.
+1. **(STARTER)** Select whether the current issue relates to, blocks, or is blocked by the issues being entered.
 
     ![Adding a related issue](img/related_issues_add_v12_8.png)
 
@@ -42,11 +49,11 @@ in the header of the related issue block.
     - same group: `project#44`
     - different group: `group/project#44`
 
-    Valid references will be added to a temporary list that you can review.
+    Valid references are added to a temporary list that you can review.
 
 1. When you have added all the related issues, click **Add** to submit.
 
-When you have finished adding all related issues, you will be able to see
+When you have finished adding all related issues, you can see
 them categorized so their relationships can be better understood visually.
 
 ![Related issue block](img/related_issue_block_v12_8.png)
@@ -56,7 +63,7 @@ them categorized so their relationships can be better understood visually.
 In the related issues block, click the "x" icon on the right-side of each issue
 token that you wish to remove.
 
-Due to the bi-directional relationship, it will no longer appear in either issue.
+Due to the bi-directional relationship, it no longer appears in either issue.
 
 ![Removing a related issue](img/related_issues_remove_v12_8.png)