help: Add docs for who can create and manage user groups.

Part of addressing #14298.

templates/zerver/help/include/sidebar_index.md

@@ -120,9 +120,10 @@
 * [Restrict stream creation](/help/configure-who-can-create-streams)
 * [Restrict stream invitation](/help/configure-who-can-invite-to-streams)
 * [Restrict private messages](/help/restrict-private-messages)
+* [Restrict user group management](/help/restrict-user-group-management)
+* [Restrict name and email changes](/help/restrict-name-and-email-changes)
 * [Change who can add custom emoji](/help/only-allow-admins-to-add-emoji)
 * [Block image and link previews](/help/allow-image-link-previews)
-* [Restrict name and email changes](/help/restrict-name-and-email-changes)
 * [Disable message edit history](/help/disable-message-edit-history)
 * [Manage editing of old messages](/help/configure-message-editing-and-deletion)
 * [Hide message content in emails](/help/hide-message-content-in-emails)

templates/zerver/help/restrict-user-group-management.md

@@ -0,0 +1,21 @@
+# Restrict user group management
+
+{!admin-only.md!}
+
+By default, all [Members](/help/roles-and-permissions) in a Zulip
+organization can create [user groups](/help/user-groups) and manage
+those they are a member of.  However, you can change your
+organization's settings to only allow administrators to create and
+manage user groups.
+
+### Change who can create and manage user groups
+
+{start_tabs}
+
+{settings_tab|organization-permissions}
+
+2. Under **Other permissions**, configure **Who can create and manage user groups**.
+
+{!save-changes.md!}
+
+{end_tabs}

templates/zerver/help/user-groups.md

@@ -42,3 +42,7 @@ any user group they are a part of. Guests cannot modify user groups.
    to save.  Zulip will notify everyone who is added or removed.
 
 {end_tabs}
+
+## Related articles
+
+* [Restrict user group management](/help/restrict-user-group-management)