From ef0b86ee6feff972de1c9870c617bf2db727aa12 Mon Sep 17 00:00:00 2001
From: Greg Grothaus <ggrothau@gmail.com>
Date: Tue, 14 Nov 2017 12:35:53 -0800
Subject: [PATCH] Validator Rollup (#12055)

* Remove warnings for non-usage of grandfathered extensions. Retain errors
for new extensions.

* Revision bump for #12015
---
 .../validator-amp-access.protoascii           |  2 +-
 .../validator-amp-accordion.protoascii        |  2 +-
 extensions/amp-ad/validator-amp-ad.protoascii |  2 +-
 .../validator-amp-analytics.protoascii        |  2 +-
 .../amp-anim/validator-amp-anim.protoascii    |  2 +-
 .../validator-amp-apester-media.protoascii    |  2 +-
 .../amp-audio/validator-amp-audio.protoascii  |  2 +-
 .../amp-bind/validator-amp-bind.protoascii    |  2 +-
 .../validator-amp-brid-player.protoascii      |  2 +-
 .../validator-amp-brightcove.protoascii       |  2 +-
 .../validator-amp-call-tracking.protoascii    |  2 +-
 .../validator-amp-carousel.protoascii         |  2 +-
 .../validator-amp-dailymotion.protoascii      |  2 +-
 .../validator-amp-experiment.protoascii       |  2 +-
 .../validator-amp-facebook.protoascii         |  2 +-
 .../validator-amp-fit-text.protoascii         |  2 +-
 .../amp-font/validator-amp-font.protoascii    |  2 +-
 .../amp-form/validator-amp-form.protoascii    |  2 +-
 .../validator-amp-fx-flying-carpet.protoascii |  2 +-
 .../validator-amp-gfycat.protoascii           |  2 +-
 .../validator-amp-iframe.protoascii           |  2 +-
 .../validator-amp-image-lightbox.protoascii   |  2 +-
 .../validator-amp-instagram.protoascii        |  2 +-
 ...dator-amp-install-serviceworker.protoascii |  2 +-
 .../validator-amp-izlesene.protoascii         |  2 +-
 .../validator-amp-jwplayer.protoascii         |  2 +-
 .../validator-amp-kaltura-player.protoascii   |  2 +-
 .../validator-amp-lightbox.protoascii         |  2 +-
 .../amp-list/validator-amp-list.protoascii    |  2 +-
 .../validator-amp-live-list.protoascii        |  2 +-
 .../validator-amp-mustache.protoascii         |  2 +-
 .../validator-amp-o2-player.protoascii        |  2 +-
 .../validator-amp-pinterest.protoascii        |  2 +-
 .../validator-amp-reach-player.protoascii     |  2 +-
 .../validator-amp-selector.protoascii         |  2 +-
 .../validator-amp-sidebar.protoascii          |  2 +-
 .../validator-amp-social-share.protoascii     |  2 +-
 .../validator-amp-soundcloud.protoascii       |  2 +-
 ...alidator-amp-springboard-player.protoascii |  2 +-
 .../validator-amp-sticky-ad.protoascii        |  2 +-
 .../validator-amp-twitter.protoascii          |  2 +-
 ...validator-amp-user-notification.protoascii |  2 +-
 .../amp-vimeo/validator-amp-vimeo.protoascii  |  2 +-
 .../amp-vine/validator-amp-vine.protoascii    |  2 +-
 .../validator-amp-youtube.protoascii          |  2 +-
 validator/engine/validator.js                 | 60 ++-----------------
 .../amp4ads_feature_tests/extensions.out      | 10 ----
 validator/testdata/feature_tests/ads.out      |  1 -
 validator/testdata/feature_tests/article.out  |  1 -
 .../feature_tests/duplicate_attribute.out     |  1 -
 .../testdata/feature_tests/extensions.out     |  1 -
 validator/testdata/feature_tests/regexps.out  |  1 -
 .../testdata/feature_tests/spec_example.out   |  1 -
 validator/validator-main.protoascii           | 16 ++---
 validator/validator.proto                     |  9 +--
 55 files changed, 58 insertions(+), 133 deletions(-)

diff --git a/extensions/amp-access/validator-amp-access.protoascii b/extensions/amp-access/validator-amp-access.protoascii
index 0630b62ca2de..1efb4cd22174 100644
--- a/extensions/amp-access/validator-amp-access.protoascii
+++ b/extensions/amp-access/validator-amp-access.protoascii
@@ -20,7 +20,7 @@ tags: {  # amp-access
     name: "amp-access"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-accordion/validator-amp-accordion.protoascii b/extensions/amp-accordion/validator-amp-accordion.protoascii
index 9b6e1e855838..c1e4f4e30959 100644
--- a/extensions/amp-accordion/validator-amp-accordion.protoascii
+++ b/extensions/amp-accordion/validator-amp-accordion.protoascii
@@ -19,7 +19,7 @@ tags: {  # amp-accordion
     name: "amp-accordion"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-ad/validator-amp-ad.protoascii b/extensions/amp-ad/validator-amp-ad.protoascii
index f8db662b0f38..84df94386e3d 100644
--- a/extensions/amp-ad/validator-amp-ad.protoascii
+++ b/extensions/amp-ad/validator-amp-ad.protoascii
@@ -38,7 +38,7 @@ tags: {  # amp-ad
     name: "amp-ad"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-analytics/validator-amp-analytics.protoascii b/extensions/amp-analytics/validator-amp-analytics.protoascii
index cc25ef332abb..1cc66e449882 100644
--- a/extensions/amp-analytics/validator-amp-analytics.protoascii
+++ b/extensions/amp-analytics/validator-amp-analytics.protoascii
@@ -23,7 +23,7 @@ tags: {  # amp-analytics
     name: "amp-analytics"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-anim/validator-amp-anim.protoascii b/extensions/amp-anim/validator-amp-anim.protoascii
index 05f15bfe3cc4..18ea3b871cf6 100644
--- a/extensions/amp-anim/validator-amp-anim.protoascii
+++ b/extensions/amp-anim/validator-amp-anim.protoascii
@@ -22,7 +22,7 @@ tags: {  # amp-anim
     name: "amp-anim"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-apester-media/validator-amp-apester-media.protoascii b/extensions/amp-apester-media/validator-amp-apester-media.protoascii
index 035655ca2332..e45b95976b3e 100644
--- a/extensions/amp-apester-media/validator-amp-apester-media.protoascii
+++ b/extensions/amp-apester-media/validator-amp-apester-media.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-apester-media
     name: "amp-apester-media"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-audio/validator-amp-audio.protoascii b/extensions/amp-audio/validator-amp-audio.protoascii
index 44c3230535d2..0c91e2af61db 100644
--- a/extensions/amp-audio/validator-amp-audio.protoascii
+++ b/extensions/amp-audio/validator-amp-audio.protoascii
@@ -20,7 +20,7 @@ tags: {  # amp-audio
     allowed_versions: "0.1"
     allowed_versions: "latest"
     deprecated_allow_duplicates: true
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
   }
   attr_lists: "common-extension-attrs"
 }
diff --git a/extensions/amp-bind/validator-amp-bind.protoascii b/extensions/amp-bind/validator-amp-bind.protoascii
index 262475dee83d..80ee385790bf 100644
--- a/extensions/amp-bind/validator-amp-bind.protoascii
+++ b/extensions/amp-bind/validator-amp-bind.protoascii
@@ -22,7 +22,7 @@ tags: {  # amp-bind
     allowed_versions: "latest"
     # amp-bind has no associated tag which indicates usage of the extension.
     # TODO(gregable): Implement a mechanism to associate attributes with
-    # extension usage and then set this to DEPRECATED_WARNING or ERROR.
+    # extension usage and then set this to GRANDFATHERED or ERROR.
     requires_usage: NONE
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-brid-player/validator-amp-brid-player.protoascii b/extensions/amp-brid-player/validator-amp-brid-player.protoascii
index c32df36f65a6..2466f5aa8461 100644
--- a/extensions/amp-brid-player/validator-amp-brid-player.protoascii
+++ b/extensions/amp-brid-player/validator-amp-brid-player.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-brid-player
     name: "amp-brid-player"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-brightcove/validator-amp-brightcove.protoascii b/extensions/amp-brightcove/validator-amp-brightcove.protoascii
index 1da3ca64533c..44124e6fe343 100644
--- a/extensions/amp-brightcove/validator-amp-brightcove.protoascii
+++ b/extensions/amp-brightcove/validator-amp-brightcove.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-brightcove
     name: "amp-brightcove"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-call-tracking/validator-amp-call-tracking.protoascii b/extensions/amp-call-tracking/validator-amp-call-tracking.protoascii
index 7d86334aabcc..a764c789fa78 100644
--- a/extensions/amp-call-tracking/validator-amp-call-tracking.protoascii
+++ b/extensions/amp-call-tracking/validator-amp-call-tracking.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-call-tracking
     name: "amp-call-tracking"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
   }
   attr_lists: "common-extension-attrs"
 }
diff --git a/extensions/amp-carousel/validator-amp-carousel.protoascii b/extensions/amp-carousel/validator-amp-carousel.protoascii
index 328ef7151f64..e4afb5012025 100644
--- a/extensions/amp-carousel/validator-amp-carousel.protoascii
+++ b/extensions/amp-carousel/validator-amp-carousel.protoascii
@@ -20,7 +20,7 @@ tags: {  # amp-carousel
     name: "amp-carousel"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-dailymotion/validator-amp-dailymotion.protoascii b/extensions/amp-dailymotion/validator-amp-dailymotion.protoascii
index 8f591f1dadc8..194a371a08d8 100644
--- a/extensions/amp-dailymotion/validator-amp-dailymotion.protoascii
+++ b/extensions/amp-dailymotion/validator-amp-dailymotion.protoascii
@@ -20,7 +20,7 @@ tags: {  # amp-dailymotion
     name: "amp-dailymotion"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-experiment/validator-amp-experiment.protoascii b/extensions/amp-experiment/validator-amp-experiment.protoascii
index c58801a1bf5d..0395326eec21 100644
--- a/extensions/amp-experiment/validator-amp-experiment.protoascii
+++ b/extensions/amp-experiment/validator-amp-experiment.protoascii
@@ -22,7 +22,7 @@ tags: {  # amp-experiment
     name: "amp-experiment"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-facebook/validator-amp-facebook.protoascii b/extensions/amp-facebook/validator-amp-facebook.protoascii
index 4a5b125c43f7..2f4f49e1b16f 100644
--- a/extensions/amp-facebook/validator-amp-facebook.protoascii
+++ b/extensions/amp-facebook/validator-amp-facebook.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-facebook
     name: "amp-facebook"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-fit-text/validator-amp-fit-text.protoascii b/extensions/amp-fit-text/validator-amp-fit-text.protoascii
index 0a923541420c..28188577d2ae 100644
--- a/extensions/amp-fit-text/validator-amp-fit-text.protoascii
+++ b/extensions/amp-fit-text/validator-amp-fit-text.protoascii
@@ -20,7 +20,7 @@ tags: {  # amp-fit-text
     name: "amp-fit-text"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-font/validator-amp-font.protoascii b/extensions/amp-font/validator-amp-font.protoascii
index 373e36fd806c..e27f993d39a6 100644
--- a/extensions/amp-font/validator-amp-font.protoascii
+++ b/extensions/amp-font/validator-amp-font.protoascii
@@ -22,7 +22,7 @@ tags: {  # amp-font
     name: "amp-font"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-form/validator-amp-form.protoascii b/extensions/amp-form/validator-amp-form.protoascii
index 501ac0a3d691..a71835953b8c 100644
--- a/extensions/amp-form/validator-amp-form.protoascii
+++ b/extensions/amp-form/validator-amp-form.protoascii
@@ -22,7 +22,7 @@ tags: {  # amp-form
     allowed_versions: "0.1"
     allowed_versions: "latest"
     deprecated_allow_duplicates: true
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
   }
   attr_lists: "common-extension-attrs"
 }
diff --git a/extensions/amp-fx-flying-carpet/validator-amp-fx-flying-carpet.protoascii b/extensions/amp-fx-flying-carpet/validator-amp-fx-flying-carpet.protoascii
index 1767ab8c27fa..d2b8f6d0dfa7 100644
--- a/extensions/amp-fx-flying-carpet/validator-amp-fx-flying-carpet.protoascii
+++ b/extensions/amp-fx-flying-carpet/validator-amp-fx-flying-carpet.protoascii
@@ -20,7 +20,7 @@ tags: {  # <script custom-element="amp-fx-flying-carpet">
     name: "amp-fx-flying-carpet"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-gfycat/validator-amp-gfycat.protoascii b/extensions/amp-gfycat/validator-amp-gfycat.protoascii
index e66424de834f..54995a7b1cf4 100644
--- a/extensions/amp-gfycat/validator-amp-gfycat.protoascii
+++ b/extensions/amp-gfycat/validator-amp-gfycat.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-gfycat
     name: "amp-gfycat"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-iframe/validator-amp-iframe.protoascii b/extensions/amp-iframe/validator-amp-iframe.protoascii
index e476078e0caf..5765cb01525f 100644
--- a/extensions/amp-iframe/validator-amp-iframe.protoascii
+++ b/extensions/amp-iframe/validator-amp-iframe.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-iframe
     name: "amp-iframe"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-image-lightbox/validator-amp-image-lightbox.protoascii b/extensions/amp-image-lightbox/validator-amp-image-lightbox.protoascii
index 02cd88cde95e..2683fd378994 100644
--- a/extensions/amp-image-lightbox/validator-amp-image-lightbox.protoascii
+++ b/extensions/amp-image-lightbox/validator-amp-image-lightbox.protoascii
@@ -20,7 +20,7 @@ tags: {  # amp-image-lightbox
     name: "amp-image-lightbox"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-instagram/validator-amp-instagram.protoascii b/extensions/amp-instagram/validator-amp-instagram.protoascii
index 5508fd468b7e..ffcca022986c 100644
--- a/extensions/amp-instagram/validator-amp-instagram.protoascii
+++ b/extensions/amp-instagram/validator-amp-instagram.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-instagram
     name: "amp-instagram"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-install-serviceworker/validator-amp-install-serviceworker.protoascii b/extensions/amp-install-serviceworker/validator-amp-install-serviceworker.protoascii
index 89e6d157ecc5..801b7f848d5e 100644
--- a/extensions/amp-install-serviceworker/validator-amp-install-serviceworker.protoascii
+++ b/extensions/amp-install-serviceworker/validator-amp-install-serviceworker.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-install-serviceworker
     name: "amp-install-serviceworker"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-izlesene/validator-amp-izlesene.protoascii b/extensions/amp-izlesene/validator-amp-izlesene.protoascii
index 00d274cfc9fd..c4cdcbaa5353 100644
--- a/extensions/amp-izlesene/validator-amp-izlesene.protoascii
+++ b/extensions/amp-izlesene/validator-amp-izlesene.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-izlesene
     name: "amp-izlesene"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
   }
   attr_lists: "common-extension-attrs"
 }
diff --git a/extensions/amp-jwplayer/validator-amp-jwplayer.protoascii b/extensions/amp-jwplayer/validator-amp-jwplayer.protoascii
index c12206bfb477..1a59217b35b5 100644
--- a/extensions/amp-jwplayer/validator-amp-jwplayer.protoascii
+++ b/extensions/amp-jwplayer/validator-amp-jwplayer.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-jwplayer
     name: "amp-jwplayer"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-kaltura-player/validator-amp-kaltura-player.protoascii b/extensions/amp-kaltura-player/validator-amp-kaltura-player.protoascii
index 08995cf335ee..589b6de3870f 100644
--- a/extensions/amp-kaltura-player/validator-amp-kaltura-player.protoascii
+++ b/extensions/amp-kaltura-player/validator-amp-kaltura-player.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-kaltura-player
     name: "amp-kaltura-player"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-lightbox/validator-amp-lightbox.protoascii b/extensions/amp-lightbox/validator-amp-lightbox.protoascii
index 1b2c0e5597f0..5d98c674ece6 100644
--- a/extensions/amp-lightbox/validator-amp-lightbox.protoascii
+++ b/extensions/amp-lightbox/validator-amp-lightbox.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-lightbox
     name: "amp-lightbox"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-list/validator-amp-list.protoascii b/extensions/amp-list/validator-amp-list.protoascii
index 11e0eb84600e..1a9dc08c0992 100644
--- a/extensions/amp-list/validator-amp-list.protoascii
+++ b/extensions/amp-list/validator-amp-list.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-list
     name: "amp-list"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-live-list/validator-amp-live-list.protoascii b/extensions/amp-live-list/validator-amp-live-list.protoascii
index f93fa331f791..9fa0e8121c83 100644
--- a/extensions/amp-live-list/validator-amp-live-list.protoascii
+++ b/extensions/amp-live-list/validator-amp-live-list.protoascii
@@ -22,7 +22,7 @@ tags: {  # amp-live-list
     name: "amp-live-list"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
   }
   attr_lists: "common-extension-attrs"
 }
diff --git a/extensions/amp-mustache/validator-amp-mustache.protoascii b/extensions/amp-mustache/validator-amp-mustache.protoascii
index e44d9e636df2..e184068cce71 100644
--- a/extensions/amp-mustache/validator-amp-mustache.protoascii
+++ b/extensions/amp-mustache/validator-amp-mustache.protoascii
@@ -27,7 +27,7 @@ tags: {  # amp-mustache
     is_custom_template: true
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-o2-player/validator-amp-o2-player.protoascii b/extensions/amp-o2-player/validator-amp-o2-player.protoascii
index 4d2513ff847e..9cbabdbd2f8d 100644
--- a/extensions/amp-o2-player/validator-amp-o2-player.protoascii
+++ b/extensions/amp-o2-player/validator-amp-o2-player.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-o2-player
     name: "amp-o2-player"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-pinterest/validator-amp-pinterest.protoascii b/extensions/amp-pinterest/validator-amp-pinterest.protoascii
index 232037c10369..d303f55a0493 100644
--- a/extensions/amp-pinterest/validator-amp-pinterest.protoascii
+++ b/extensions/amp-pinterest/validator-amp-pinterest.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-pinterest
     name: "amp-pinterest"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-reach-player/validator-amp-reach-player.protoascii b/extensions/amp-reach-player/validator-amp-reach-player.protoascii
index 06c1479fa180..e6027c86bcf9 100644
--- a/extensions/amp-reach-player/validator-amp-reach-player.protoascii
+++ b/extensions/amp-reach-player/validator-amp-reach-player.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-reach-player
     name: "amp-reach-player"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-selector/validator-amp-selector.protoascii b/extensions/amp-selector/validator-amp-selector.protoascii
index fe4601d69b46..60834a3bea24 100644
--- a/extensions/amp-selector/validator-amp-selector.protoascii
+++ b/extensions/amp-selector/validator-amp-selector.protoascii
@@ -20,7 +20,7 @@ tags: {
     name: "amp-selector"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
   }
   attr_lists: "common-extension-attrs"
 }
diff --git a/extensions/amp-sidebar/validator-amp-sidebar.protoascii b/extensions/amp-sidebar/validator-amp-sidebar.protoascii
index a516ed35e8f6..03d9bc24f511 100644
--- a/extensions/amp-sidebar/validator-amp-sidebar.protoascii
+++ b/extensions/amp-sidebar/validator-amp-sidebar.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-sidebar
     name: "amp-sidebar"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-social-share/validator-amp-social-share.protoascii b/extensions/amp-social-share/validator-amp-social-share.protoascii
index 2b545f81b663..4f9f82f0a614 100644
--- a/extensions/amp-social-share/validator-amp-social-share.protoascii
+++ b/extensions/amp-social-share/validator-amp-social-share.protoascii
@@ -22,7 +22,7 @@ tags: {  # amp-social-share
     name: "amp-social-share"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-soundcloud/validator-amp-soundcloud.protoascii b/extensions/amp-soundcloud/validator-amp-soundcloud.protoascii
index 7f3dab83bb80..d28ac345a302 100644
--- a/extensions/amp-soundcloud/validator-amp-soundcloud.protoascii
+++ b/extensions/amp-soundcloud/validator-amp-soundcloud.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-soundcloud
     name: "amp-soundcloud"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-springboard-player/validator-amp-springboard-player.protoascii b/extensions/amp-springboard-player/validator-amp-springboard-player.protoascii
index 54bca218e823..8b3cc9f69947 100644
--- a/extensions/amp-springboard-player/validator-amp-springboard-player.protoascii
+++ b/extensions/amp-springboard-player/validator-amp-springboard-player.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-springboard-player
     name: "amp-springboard-player"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-sticky-ad/validator-amp-sticky-ad.protoascii b/extensions/amp-sticky-ad/validator-amp-sticky-ad.protoascii
index 1bf02423c255..c5cd44f7d0be 100644
--- a/extensions/amp-sticky-ad/validator-amp-sticky-ad.protoascii
+++ b/extensions/amp-sticky-ad/validator-amp-sticky-ad.protoascii
@@ -22,7 +22,7 @@ tags: {  # <script custom-element="amp-sticky-ad">
     allowed_versions: "1.0"
     allowed_versions: "latest"
     deprecated_versions: "0.1"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
   }
   attr_lists: "common-extension-attrs"
 }
diff --git a/extensions/amp-twitter/validator-amp-twitter.protoascii b/extensions/amp-twitter/validator-amp-twitter.protoascii
index d6f21d5c47a0..790afc6f3be4 100644
--- a/extensions/amp-twitter/validator-amp-twitter.protoascii
+++ b/extensions/amp-twitter/validator-amp-twitter.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-twitter
     name: "amp-twitter"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-user-notification/validator-amp-user-notification.protoascii b/extensions/amp-user-notification/validator-amp-user-notification.protoascii
index 596f72519ca4..b1afa20433f5 100644
--- a/extensions/amp-user-notification/validator-amp-user-notification.protoascii
+++ b/extensions/amp-user-notification/validator-amp-user-notification.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-user-notification
     name: "amp-user-notification"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-vimeo/validator-amp-vimeo.protoascii b/extensions/amp-vimeo/validator-amp-vimeo.protoascii
index af01f05f15c1..b1da868ca3dc 100644
--- a/extensions/amp-vimeo/validator-amp-vimeo.protoascii
+++ b/extensions/amp-vimeo/validator-amp-vimeo.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-vimeo
     name: "amp-vimeo"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-vine/validator-amp-vine.protoascii b/extensions/amp-vine/validator-amp-vine.protoascii
index 7e6e2e0f7d5e..26a694a5a73a 100644
--- a/extensions/amp-vine/validator-amp-vine.protoascii
+++ b/extensions/amp-vine/validator-amp-vine.protoascii
@@ -21,7 +21,7 @@ tags: {  # amp-vine
     name: "amp-vine"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/extensions/amp-youtube/validator-amp-youtube.protoascii b/extensions/amp-youtube/validator-amp-youtube.protoascii
index c7c4f043ea0e..b49666c0bc20 100644
--- a/extensions/amp-youtube/validator-amp-youtube.protoascii
+++ b/extensions/amp-youtube/validator-amp-youtube.protoascii
@@ -20,7 +20,7 @@ tags: {  # amp-youtube
     name: "amp-youtube"
     allowed_versions: "0.1"
     allowed_versions: "latest"
-    requires_usage: DEPRECATED_WARNING
+    requires_usage: GRANDFATHERED
     deprecated_allow_duplicates: true
   }
   attr_lists: "common-extension-attrs"
diff --git a/validator/engine/validator.js b/validator/engine/validator.js
index e580d32b334f..65d966b671be 100644
--- a/validator/engine/validator.js
+++ b/validator/engine/validator.js
@@ -1974,11 +1974,9 @@ class ExtensionsContext {
   constructor() {
     // |extensionsLoaded_| tracks the valid <script> tags loading
     // amp extensions which were seen in the document's head. Most extensions
-    // are also added to either |extensionsUnusedRequired_| or
-    // |extensionsUnusedWarning_| when encountered in the head.
-    // When a tag is seen later in the document which makes use of an
-    // extension, that extension, the extension is recorded in
-    // |extensionsUsed_|.
+    // are also added to |extensionsUnusedRequired_| when encountered in the
+    // head. When a tag is seen later in the document which makes use of an
+    // extension, that extension is recorded in |extensionsUsed_|.
 
     /**
      * Used as a set, based on key names.
@@ -1998,12 +1996,6 @@ class ExtensionsContext {
      */
     this.extensionsUnusedRequired_ = [];
 
-    /**
-     * @type {!Array<string>}
-     * @private
-     */
-    this.extensionsUnusedWarning_ = [];
-
     /**
      * Used as a set, based on key names.
      * @type {!Object<string, boolean>}
@@ -2046,16 +2038,6 @@ class ExtensionsContext {
     this.extensionsUnusedRequired_.push(extension);
   }
 
-  /**
-   * Record that a loaded extension indicates a new non-fatal requirement:
-   * namely that some tag must make use of this extension. This results in
-   * a warning.
-   * @param {string} extension
-   */
-  recordExtensionUnusedWarning(extension) {
-    this.extensionsUnusedWarning_.push(extension);
-  }
-
   /**
    * Returns false if the named extension has not yet been loaded. Note that
    * this assumes that all extensions will be loaded in the document earlier
@@ -2140,20 +2122,6 @@ class ExtensionsContext {
     out.sort();
     return out;
   }
-
-  /**
-   * Returns a list of unused extensions which produce validation warnings
-   * when unused.
-   * @return {!Array<string>}
-   */
-  unusedExtensionsWarning() {
-    // Compute Difference: extensionsUnusedWarning_ - extensionsUsed_
-    var out = [];
-    for (const extension of this.extensionsUnusedWarning_)
-      if (!(extension in this.extensionsUsed_)) out.push(extension);
-    out.sort();
-    return out;
-  }
 }
 
 
@@ -4280,9 +4248,7 @@ function validateTagAgainstSpec(
     extensionsCtx.recordExtensionLoaded(extensionName);
     switch (extensionSpec.requiresUsage) {
       case amp.validator.ExtensionSpec.ExtensionUsageRequirement
-          .DEPRECATED_WARNING:
-        extensionsCtx.recordExtensionUnusedWarning(extensionName);
-        break;
+          .GRANDFATHERED:  // Fallthrough intended:
       case amp.validator.ExtensionSpec.ExtensionUsageRequirement.NONE:
         // This extension does not have usage demonstrated by a tag, for
         // example: amp-dynamic-css-classes
@@ -4789,22 +4755,6 @@ class ParsedValidatorRules {
             /* specUrl */ '', validationResult);
       }
     }
-
-    if (!amp.validator.LIGHT) {
-      let unusedWarning = extensionsCtx.unusedExtensionsWarning();
-      for (const unusedExtensionName of unusedWarning) {
-        context.addError(
-            amp.validator.ValidationError.Severity.WARNING,
-            amp.validator.ValidationError.Code.WARNING_EXTENSION_UNUSED,
-            context.getDocLocator(),
-            /* params */
-            [
-              unusedExtensionName,
-              this.exampleTagForExtension(unusedExtensionName)
-            ],
-            /* specUrl */ '', validationResult);
-      }
-    }
   }
 
   /**
@@ -5820,8 +5770,6 @@ amp.validator.categorizeError = function(error) {
   // use 'data-shortcode' instead."
   if (error.code === amp.validator.ValidationError.Code.DEPRECATED_ATTR ||
       error.code === amp.validator.ValidationError.Code.DEPRECATED_TAG ||
-      error.code ===
-          amp.validator.ValidationError.Code.WARNING_EXTENSION_UNUSED ||
       error.code ===
           amp.validator.ValidationError.Code
               .WARNING_EXTENSION_DEPRECATED_VERSION ||
diff --git a/validator/testdata/amp4ads_feature_tests/extensions.out b/validator/testdata/amp4ads_feature_tests/extensions.out
index 0af91a81d7b6..59a831be9072 100644
--- a/validator/testdata/amp4ads_feature_tests/extensions.out
+++ b/validator/testdata/amp4ads_feature_tests/extensions.out
@@ -31,13 +31,3 @@ amp4ads_feature_tests/extensions.html:111:2 Only AMP runtime 'script' tags are a
 amp4ads_feature_tests/extensions.html:113:2 Only AMP runtime 'script' tags are allowed, and only in the document head. (see https://www.ampproject.org/docs/reference/spec#html-tags) [CUSTOM_JAVASCRIPT_DISALLOWED]
 amp4ads_feature_tests/extensions.html:118:2 Only AMP runtime 'script' tags are allowed, and only in the document head. (see https://www.ampproject.org/docs/reference/spec#html-tags) [CUSTOM_JAVASCRIPT_DISALLOWED]
 amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-animation' was found on this page, but is unused. Please remove this extension. [AMP_TAG_PROBLEM]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-accordion' was found on this page, but is unused (no 'amp-accordion' tag seen). This may become an error in the future. [DEPRECATION]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-analytics' was found on this page, but is unused (no 'amp-analytics' tag seen). This may become an error in the future. [DEPRECATION]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-anim' was found on this page, but is unused (no 'amp-anim' tag seen). This may become an error in the future. [DEPRECATION]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-audio' was found on this page, but is unused (no 'amp-audio (A4A)' tag seen). This may become an error in the future. [DEPRECATION]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-carousel' was found on this page, but is unused (no 'amp-carousel' tag seen). This may become an error in the future. [DEPRECATION]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-fit-text' was found on this page, but is unused (no 'amp-fit-text' tag seen). This may become an error in the future. [DEPRECATION]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-font' was found on this page, but is unused (no 'amp-font' tag seen). This may become an error in the future. [DEPRECATION]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-form' was found on this page, but is unused (no 'FORM [method=POST]' tag seen). This may become an error in the future. [DEPRECATION]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-social-share' was found on this page, but is unused (no 'amp-social-share' tag seen). This may become an error in the future. [DEPRECATION]
-amp4ads_feature_tests/extensions.html:121:20 The extension 'amp-youtube' was found on this page, but is unused (no 'amp-youtube' tag seen). This may become an error in the future. [DEPRECATION]
diff --git a/validator/testdata/feature_tests/ads.out b/validator/testdata/feature_tests/ads.out
index 375d389043b6..7ef22e9a431a 100644
--- a/validator/testdata/feature_tests/ads.out
+++ b/validator/testdata/feature_tests/ads.out
@@ -1,2 +1 @@
 PASS
-feature_tests/ads.html:1334:7 The extension 'amp-analytics' was found on this page, but is unused (no 'amp-analytics' tag seen). This may become an error in the future. [DEPRECATION]
diff --git a/validator/testdata/feature_tests/article.out b/validator/testdata/feature_tests/article.out
index 99fc46ac680a..ad9a122e51ac 100644
--- a/validator/testdata/feature_tests/article.out
+++ b/validator/testdata/feature_tests/article.out
@@ -1,4 +1,3 @@
 FAIL
 feature_tests/article.html:287:2 The tag 'content' is disallowed. [DISALLOWED_HTML]
 feature_tests/article.html:498:7 The tag 'amp-video extension .js script' is missing or incorrect, but required by 'amp-video'. This will soon be an error. (see https://www.ampproject.org/docs/reference/components/amp-video) [DEPRECATION]
-feature_tests/article.html:498:7 The extension 'amp-analytics' was found on this page, but is unused (no 'amp-analytics' tag seen). This may become an error in the future. [DEPRECATION]
diff --git a/validator/testdata/feature_tests/duplicate_attribute.out b/validator/testdata/feature_tests/duplicate_attribute.out
index 7eb693d658e2..cc16500f9c21 100644
--- a/validator/testdata/feature_tests/duplicate_attribute.out
+++ b/validator/testdata/feature_tests/duplicate_attribute.out
@@ -8,4 +8,3 @@ feature_tests/duplicate_attribute.html:38:3 The tag 'amp-img' contains the attri
 feature_tests/duplicate_attribute.html:41:3 The tag 'script' contains the attribute 'type' repeated multiple times. [DISALLOWED_HTML]
 feature_tests/duplicate_attribute.html:42:3 The tag 'script' contains the attribute 'type' repeated multiple times. [DISALLOWED_HTML]
 feature_tests/duplicate_attribute.html:42:3 Only AMP runtime 'script' tags are allowed, and only in the document head. (see https://www.ampproject.org/docs/reference/spec#html-tags) [CUSTOM_JAVASCRIPT_DISALLOWED]
-feature_tests/duplicate_attribute.html:45:7 The extension 'amp-image-lightbox' was found on this page, but is unused (no 'amp-image-lightbox' tag seen). This may become an error in the future. [DEPRECATION]
diff --git a/validator/testdata/feature_tests/extensions.out b/validator/testdata/feature_tests/extensions.out
index 4c2dcbefa02b..6b557cc20862 100644
--- a/validator/testdata/feature_tests/extensions.out
+++ b/validator/testdata/feature_tests/extensions.out
@@ -2,4 +2,3 @@ FAIL
 feature_tests/extensions.html:42:2 The tag 'amp-analytics' requires including the 'amp-analytics' extension JavaScript. (see https://www.ampproject.org/docs/reference/components/amp-analytics) [AMP_TAG_PROBLEM]
 feature_tests/extensions.html:43:4 The tag 'amp-analytics extension .json script' requires including the 'amp-analytics' extension JavaScript. (see https://www.ampproject.org/docs/reference/components/amp-analytics) [AMP_TAG_PROBLEM]
 feature_tests/extensions.html:48:7 The extension 'amp-timeago' was found on this page, but is unused. Please remove this extension. [AMP_TAG_PROBLEM]
-feature_tests/extensions.html:48:7 The extension 'amp-ad' was found on this page, but is unused (no 'amp-ad' tag seen). This may become an error in the future. [DEPRECATION]
diff --git a/validator/testdata/feature_tests/regexps.out b/validator/testdata/feature_tests/regexps.out
index 5bb5a92b93ab..da87c8691107 100644
--- a/validator/testdata/feature_tests/regexps.out
+++ b/validator/testdata/feature_tests/regexps.out
@@ -23,4 +23,3 @@ feature_tests/regexps.html:139:2 The attribute 'name' in tag 'input' is set to t
 feature_tests/regexps.html:140:2 The attribute 'name' in tag 'input' is set to the invalid value 'webkitRequestFullscreen'. (see https://www.ampproject.org/docs/reference/components/amp-form) [DISALLOWED_HTML]
 feature_tests/regexps.html:143:7 The tag 'head > style[amp-boilerplate]' is missing or incorrect, but required by 'noscript > style[amp-boilerplate]'. (see https://github.com/ampproject/amphtml/blob/master/spec/amp-boilerplate.md) [GENERIC]
 feature_tests/regexps.html:143:7 The extension 'amp-hulu' was found on this page, but is unused. Please remove this extension. [AMP_TAG_PROBLEM]
-feature_tests/regexps.html:143:7 The extension 'amp-vine' was found on this page, but is unused (no 'amp-vine' tag seen). This may become an error in the future. [DEPRECATION]
diff --git a/validator/testdata/feature_tests/spec_example.out b/validator/testdata/feature_tests/spec_example.out
index 219809ddf92c..d470e87b1b5a 100644
--- a/validator/testdata/feature_tests/spec_example.out
+++ b/validator/testdata/feature_tests/spec_example.out
@@ -1,3 +1,2 @@
 PASS
 feature_tests/spec_example.html:59:7 The tag 'amp-ad extension .js script' is missing or incorrect, but required by 'amp-ad'. This will soon be an error. (see https://www.ampproject.org/docs/reference/components/amp-ad) [DEPRECATION]
-feature_tests/spec_example.html:59:7 The extension 'amp-carousel' was found on this page, but is unused (no 'amp-carousel' tag seen). This may become an error in the future. [DEPRECATION]
diff --git a/validator/validator-main.protoascii b/validator/validator-main.protoascii
index 54a00fb34c97..f8dbc941c10d 100644
--- a/validator/validator-main.protoascii
+++ b/validator/validator-main.protoascii
@@ -20,12 +20,12 @@
 # in production from crashing. This id is not relevant to validator.js
 # because thus far, engine (validator.js) and spec file
 # (validator-main.protoascii) are always released together.
-min_validator_revision_required: 246
+min_validator_revision_required: 265
 # The spec file revision allows the validator engine to distinguish
 # newer versions of the spec file. This is currently a Google internal
 # mechanism, validator.js does not use this facility. However, any
 # change to this file (validator-main.js) requires updating this revision id.
-spec_file_revision: 517
+spec_file_revision: 520
 
 styles_spec_url: "https://www.ampproject.org/docs/guides/author-develop/responsive/style_pages"
 script_spec_url: "https://www.ampproject.org/docs/reference/spec#html-tags"
@@ -1136,8 +1136,6 @@ attr_lists: {
   }
 }
 tags: {
-  html_format: AMP
-  html_format: AMP4ADS
   tag_name: "BLOCKQUOTE"
   attrs: { name: "align" }
   attr_lists: "cite-attr"
@@ -1311,8 +1309,6 @@ tags: {
 }
 # 4.5.7 The q element
 tags: {
-  html_format: AMP
-  html_format: AMP4ADS
   tag_name: "Q"
   attr_lists: "cite-attr"
 }
@@ -1419,8 +1415,6 @@ tags: {
 # 4.6 Edits
 # 4.6.1 The ins element
 tags: {
-  html_format: AMP
-  html_format: AMP4ADS
   tag_name: "INS"
   # https://developer.mozilla.org/en-US/docs/Web/HTML/Element/ins
   # These attributes have specific formatting, but as they are metadata
@@ -1431,8 +1425,6 @@ tags: {
 }
 # 4.6.2 The del element
 tags: {
-  html_format: AMP
-  html_format: AMP4ADS
   tag_name: "DEL"
   # https://developer.mozilla.org/en-US/docs/Web/HTML/Element/del
   # These attributes have specific formatting, but as they are metadata
@@ -4000,11 +3992,11 @@ error_specificity {
 }
 error_specificity {
   code: CSS_SYNTAX_PROPERTY_REQUIRES_QUALIFICATION
-  specificity: 75
+  specificity: 76
 }
 error_specificity {
   code: BASE_TAG_MUST_PRECEED_ALL_URLS
-  specificity: 75
+  specificity: 76
 }
 error_specificity { code: DISALLOWED_SCRIPT_TAG specificity: 100 }
 error_specificity { code: GENERAL_DISALLOWED_TAG specificity: 101 }
diff --git a/validator/validator.proto b/validator/validator.proto
index 2926c6edfb2f..5c31fcffad53 100644
--- a/validator/validator.proto
+++ b/validator/validator.proto
@@ -341,15 +341,16 @@ message ExtensionSpec {
   //
   // The second requirement (extension requires usage) has a few exceptions:
   //   1) For older extensions, implemented before these tagspec rules, we
-  //      do not want to introduce a breaking change, so we emit a warning
-  //      rather than an error if there is an unused extension. New extensions
-  //      may not make this requirement a warning.
+  //      do not want to introduce a breaking change, so we grandfather these
+  //      extensions to not require usage. New extensions must use ERROR.
   //   2) Some extensions, such as `amp-dynamic-css-classes`, do not have any
   //      associated tag in the document indicating usage. These extensions do
   //      not trigger warnings or errors.
   enum ExtensionUsageRequirement {
     ERROR = 1;
-    DEPRECATED_WARNING = 2;
+    // Exception for grandfathered extensions. #1 above.
+    GRANDFATHERED = 2;
+    // Exception for extensions with no usage-indicating tag. #2 above.
     NONE = 3;
   }
   optional ExtensionUsageRequirement requires_usage = 7 [default = ERROR];