Negotiator amends: Make it possible to disable Preview links in the CMS

Existing functionality is limited to `RedirectorPage`

Another option would be to use the HiddenClass methodology

code/Controllers/SilverStripeNavigatorItem_LiveLink.php

@@ -58,11 +58,20 @@ class SilverStripeNavigatorItem_LiveLink extends SilverStripeNavigatorItem
             $record->hasExtension(Versioned::class)
             && $record->hasStages()
             && $this->getLivePage()
-            // Don't follow redirects in preview, they break the CMS editing form
+            && $this->showLiveLink()
-            && !($this->record instanceof RedirectorPage)
         );
     }
 
+    public function showLiveLink()
+    {
+        try {
+            return $this->record->config()->get('show_live_link');
+        } catch (\BadMethodCallException $e) {
+            // Not using `config()` or similar
+            return false;
+        }
+    }
+
     public function isActive()
     {
         return (

code/Controllers/SilverStripeNavigatorItem_StageLink.php

@@ -64,11 +64,20 @@ class SilverStripeNavigatorItem_StageLink extends SilverStripeNavigatorItem
             $record->hasExtension(Versioned::class)
             && $record->hasStages()
             && $this->getDraftPage()
-            // Don't follow redirects in preview, they break the CMS editing form
+            && $this->showStageLink()
-            && !($record instanceof RedirectorPage)
         );
     }
 
+    public function showStageLink()
+    {
+        try {
+            return $this->record->config()->get('show_stage_link');
+        } catch (\BadMethodCallException $e) {
+            // Not using `config()` or similar
+            return false;
+        }
+    }
+
     public function isActive()
     {
         return (

code/Model/RedirectorPage.php

@@ -24,6 +24,10 @@ class RedirectorPage extends Page
 
     private static $icon_class = 'font-icon-p-redirect';
 
+    private static $show_stage_link = false;
+
+    private static $show_live_link = false;
+
     private static $db = array(
         "RedirectionType" => "Enum('Internal,External','Internal')",
         "ExternalURL" => "Varchar(2083)" // 2083 is the maximum length of a URL in Internet Explorer.

code/Model/SiteTree.php

@@ -137,6 +137,10 @@ class SiteTree extends DataObject implements PermissionProvider, i18nEntityProvi
      */
     protected static $_allowedChildren = array();
 
+    private static $show_stage_link = true;
+
+    private static $show_live_link = true;
+
     /**
      * The default child class for this page.
      * Note: Value might be cached, see {@link $allowed_chilren}.