Remove outdated GitLab versions from Editor docs

doc/administration/merge_request_diffs.md

 ---
 stage: Create
 group: Editor
-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/#assignments"
-type: reference
+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/#assignments
 ---
 
 # Merge request diffs storage **(FREE SELF)**
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/52568) in GitLab 11.8.
-
 Merge request diffs are size-limited copies of diffs associated with merge
 requests. When viewing a merge request, diffs are sourced from these copies
 wherever possible as a performance optimization.

doc/api/project_snippets.md

 ---
 stage: Create
 group: Editor
-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/#assignments"
-type: reference, api
+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/#assignments
 ---
 
 # Project snippets **(FREE)**
@@ -247,8 +246,6 @@ curl "https://gitlab.com/api/v4/projects/1/snippets/2/files/master/snippet%2Erb/
 
 ## Get user agent details
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/29508) in GitLab 9.4.
-
 Available only for users with the Administrator [role](../user/permissions.md).
 
 ```plaintext

doc/api/snippets.md

 ---
 stage: Create
 group: Editor
-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/#assignments"
-type: reference, api
+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/#assignments
 ---
 
 # Snippets API **(FREE)**
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/6373) in GitLab 8.15.
-
 Snippets API operates on [snippets](../user/snippets.md). Related APIs exist for
 [project snippets](project_snippets.md) and
 [moving snippets between storages](snippet_repository_storage_moves.md).
@@ -449,8 +446,6 @@ Example response:
 
 ## Get user agent details
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/12655) in GitLab 9.4.
-
 NOTE:
 Available only for administrators.
 

doc/api/wikis.md

 ---
 stage: Create
 group: Editor
-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/#assignments"
-type: reference, api
+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/#assignments
 ---
 
 # Project wikis API **(FREE)**
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/13372) in GitLab 10.0.
-
 The project [wikis](../user/project/wiki/index.md) API is available only in APIv4.
 An API for [group wikis](group_wikis.md) is also available.
 

doc/development/wikis.md

 ---
-type: reference, dev
 stage: Create
 group: Editor
 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/#assignments
@@ -91,8 +90,6 @@ Only some data is persisted in the database:
 
 The web UI uploads attachments through the REST API, which stores the files as commits in the wiki repository.
 
-Prior to GitLab 11.3 attachments were stored outside of the repository, [see this issue](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/33475).
-
 ## Related topics
 
 - [Gollum installation instructions](https://github.com/gollum/gollum/wiki/Installation)

doc/user/project/repository/web_editor.md

@@ -2,7 +2,6 @@
 stage: Create
 group: Editor
 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/#assignments
-type: howto
 ---
 
 # GitLab Web Editor **(FREE)**
@@ -118,8 +117,6 @@ There are multiple ways to create a branch from the GitLab web interface.
 
 ### Create a new branch from an issue
 
-> [Introduced](https://gitlab.com/gitlab-org/gitlab-foss/-/merge_requests/2808) in GitLab 8.6.
-
 If your development workflow requires an issue for every merge
 request, you can create a branch directly from the issue to speed the process up.
 The new branch, and later its merge request, are marked as related to this issue.

doc/user/project/wiki/index.md

 ---
 stage: Create
 group: Editor
-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/#assignments"
-type: reference, how-to
+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/#assignments
 ---
 
 # Wiki **(FREE)**
@@ -87,11 +86,7 @@ Users with the [Developer role](../../permissions.md) can create new wiki pages:
    [special characters](#special-characters-in-page-titles) for subdirectories and formatting,
    and have [length restrictions](#length-restrictions-for-file-and-directory-names).
 1. Add content to your wiki page.
-1. Optional. Attach a file, and GitLab stores it according to your installed version of GitLab:
-   - *Files added in [GitLab 11.3 and later](https://gitlab.com/gitlab-org/gitlab-foss/-/issues/33475):*
-     Files are stored in the wiki's Git repository.
-   - *Files added GitLab 11.2 and earlier:* Files are stored in GitLab itself. To add
-     the file to the wiki's Git repository, you must re-upload the file.
+1. Optional. Attach a file, and GitLab stores it in the wiki's Git repository.
 1. Add a **Commit message**. Git requires a commit message, so GitLab creates one
    if you don't enter one yourself.
 1. Select **Create page**.
@@ -227,9 +222,9 @@ You can see the changes made in a version of a wiki page, similar to versioned d
 
 ## Track wiki events
 
-> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/14902) in **GitLab 12.10.**
-> - Git events were [introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/216014) in **GitLab 13.0.**
-> - [Feature flag for Git events was removed](https://gitlab.com/gitlab-org/gitlab/-/issues/258665) in **GitLab 13.5**
+> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/14902) in GitLab 12.10.
+> - Git events were [introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/216014) in GitLab 13.0.
+> - [Feature flag for Git events was removed](https://gitlab.com/gitlab-org/gitlab/-/issues/258665) in GitLab 13.5.
 
 GitLab tracks wiki creation, deletion, and update events. These events are displayed on these pages:
 

doc/user/search/index.md

 ---
 stage: Create
 group: Editor
-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/#assignments"
-type: index, reference, howto
+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/#assignments
 ---
 
 # Searching in GitLab **(FREE)**
@@ -102,8 +101,7 @@ You can filter the **Issues** list to individual instances by their ID. For exam
 
 ### Filtering merge requests by approvers **(PREMIUM)**
 
-> - [Introduced](https://gitlab.com/gitlab-org/gitlab/-/merge_requests/9468) in GitLab 11.9.
-> - Moved to GitLab Premium in 13.9.
+> Moved to GitLab Premium in 13.9.
 
 To filter merge requests by an individual approver, you can type (or select from
 the dropdown) **Approver** and select the user.