diff --git a/extensions/amp-story/0.1/page-scaling.js b/extensions/amp-story/0.1/page-scaling.js
index a586c0fa745e..93e0c7532972 100644
--- a/extensions/amp-story/0.1/page-scaling.js
+++ b/extensions/amp-story/0.1/page-scaling.js
@@ -209,7 +209,8 @@ export class PageScalingService {
       } else if (Services.platformFor(win).isFirefox()) {
         // Firefox does not support `zoom`.
         // TODO(alanorozco): Use `scale` on Firefox.
-        user().warn('`amp-story-scaling` ignored: Firefox is not supported.');
+        user().warn('AMP-STORY',
+            '`amp-story-scaling` ignored: Firefox is not supported.');
         pageScalingService = MOCK_PAGE_SCALING_SERVICE;
       } else {
         pageScalingService = new PageScalingService(win, story);
diff --git a/tools/experiments/experiments.js b/tools/experiments/experiments.js
index ffe5abb2a03d..d5afc7fe5188 100644
--- a/tools/experiments/experiments.js
+++ b/tools/experiments/experiments.js
@@ -269,6 +269,12 @@ const EXPERIMENTS = [
     spec: 'https://github.com/ampproject/amphtml/issues/11329',
     cleanupIssue: 'https://github.com/ampproject/amphtml/issues/11475',
   },
+  {
+    id: 'amp-story-scaling',
+    name: 'Enables dynamic page scaling in amp-story',
+    spec: 'https://github.com/ampproject/amphtml/issues/12902',
+    cleanupIssue: 'https://github.com/ampproject/amphtml/issues/12902',
+  },
   {
     id: 'disable-amp-story-desktop',
     name: 'Disables responsive desktop experience for the amp-story component',