Added email stability feature flag

no issue

ghost/admin/app/services/feature.js

@@ -63,6 +63,7 @@ export default class FeatureService extends Service {
     @feature('lexicalEditor') lexicalEditor;
     @feature('audienceFeedback') audienceFeedback;
     @feature('suppressionList') suppressionList;
+    @feature('emailStability') emailStability;
 
     _user = null;
 

ghost/admin/app/templates/settings/labs.hbs

@@ -213,6 +213,19 @@
                         </div>
                     </div>
                 </div>
+                <div class="gh-expandable-block">
+                    <div class="gh-expandable-header">
+                        <div>
+                            <h4 class="gh-expandable-title">Email stability</h4>
+                            <p class="gh-expandable-description">
+                                Use a new email sending flow that improves how email errors are handled.
+                            </p>
+                        </div>
+                        <div class="for-switch">
+                            <GhFeatureFlag @flag="emailStability" />
+                        </div>
+                    </div>
+                </div>
             </div>
         </div>
         {{/if}}

ghost/core/core/shared/labs.js

@@ -30,7 +30,8 @@ const ALPHA_FEATURES = [
     'urlCache',
     'beforeAfterCard',
     'lexicalEditor',
-    'suppressionList'
+    'suppressionList',
+    'emailStability'
 ];
 
 module.exports.GA_KEYS = [...GA_FEATURES];