UX: reviving old topic popup should not have red warning background

app/assets/stylesheets/desktop/compose.scss

@@ -29,6 +29,10 @@
     background: dark-light-diff($danger, $secondary, 50%, -40%);
   }
 
+  &.old-topic {
+    background-color: dark-light-diff($tertiary, $secondary, 85%, -65%);
+  }
+
   h3 {
     margin-bottom: 10px;
   }

lib/composer_messages_finder.rb

@@ -149,7 +149,7 @@ class ComposerMessagesFinder
     {
       templateName: 'composer/education',
       wait_for_typing: false,
-      extraClass: 'urgent',
+      extraClass: 'old-topic',
       body: PrettyText.cook(I18n.t('education.reviving_old_topic', days: (Time.zone.now - topic.last_posted_at).round / 1.day))
     }
   end