diff --git a/testing/web-platform/tests/storage/estimate-indexeddb.https.any.js b/testing/web-platform/tests/storage/estimate-indexeddb.https.any.js
index 7e84ae0f0ee12..43511e29a9bd0 100644
--- a/testing/web-platform/tests/storage/estimate-indexeddb.https.any.js
+++ b/testing/web-platform/tests/storage/estimate-indexeddb.https.any.js
@@ -27,144 +27,37 @@ resources
 util
 .
 js
-test
-(
-t
-=
->
-{
-assert_true
-(
-'
-estimate
-'
-in
-navigator
-.
-storage
-)
-;
-assert_equals
-(
-typeof
-navigator
-.
-storage
-.
-estimate
-'
-function
-'
-)
-;
-assert_true
-(
-navigator
-.
-storage
+/
+/
+Technically
+this
+verifies
+unspecced
+behavior
 .
-estimate
-(
-)
-instanceof
-Promise
-)
-;
-}
-'
-estimate
-(
-)
-method
-exists
-and
-returns
-a
-Promise
-'
-)
-;
-promise_test
-(
-async
-t
-=
->
-{
-const
-estimate
-=
-await
-navigator
+See
+/
+/
+https
+:
+/
+/
+github
 .
+com
+/
+whatwg
+/
 storage
+/
+issues
+/
+110
+for
+defining
+this
+behavior
 .
-estimate
-(
-)
-;
-assert_equals
-(
-typeof
-estimate
-'
-object
-'
-)
-;
-assert_true
-(
-'
-usage
-'
-in
-estimate
-)
-;
-assert_equals
-(
-typeof
-estimate
-.
-usage
-'
-number
-'
-)
-;
-assert_true
-(
-'
-quota
-'
-in
-estimate
-)
-;
-assert_equals
-(
-typeof
-estimate
-.
-quota
-'
-number
-'
-)
-;
-}
-'
-estimate
-(
-)
-resolves
-to
-dictionary
-with
-members
-'
-)
-;
 promise_test
 (
 async
diff --git a/testing/web-platform/tests/storage/storagemanager-estimate.https.any.js b/testing/web-platform/tests/storage/storagemanager-estimate.https.any.js
index 3e3f076c40c22..d3cc652221420 100644
--- a/testing/web-platform/tests/storage/storagemanager-estimate.https.any.js
+++ b/testing/web-platform/tests/storage/storagemanager-estimate.https.any.js
@@ -11,13 +11,36 @@ estimate
 )
 test
 (
-function
-(
 t
-)
+=
+>
 {
 assert_true
 (
+'
+estimate
+'
+in
+navigator
+.
+storage
+)
+;
+assert_equals
+(
+typeof
+navigator
+.
+storage
+.
+estimate
+'
+function
+'
+)
+;
+assert_true
+(
 navigator
 .
 storage
@@ -35,6 +58,8 @@ estimate
 (
 )
 method
+exists
+and
 returns
 a
 Promise
@@ -43,12 +68,15 @@ Promise
 ;
 promise_test
 (
-function
-(
+async
 t
-)
+=
+>
 {
-return
+const
+result
+=
+await
 navigator
 .
 storage
@@ -56,14 +84,7 @@ storage
 estimate
 (
 )
-.
-then
-(
-function
-(
-result
-)
-{
+;
 assert_equals
 (
 typeof
@@ -114,9 +135,6 @@ number
 )
 ;
 }
-)
-;
-}
 '
 estimate
 (
@@ -129,342 +147,3 @@ members
 '
 )
 ;
-promise_test
-(
-function
-(
-t
-)
-{
-const
-large_value
-=
-new
-Uint8Array
-(
-1e6
-)
-;
-const
-dbname
-=
-db
--
-{
-location
-}
--
-{
-t
-.
-name
-}
-;
-let
-db
-before
-after
-;
-indexedDB
-.
-deleteDatabase
-(
-dbname
-)
-;
-return
-new
-Promise
-(
-(
-resolve
-reject
-)
-=
->
-{
-const
-open
-=
-indexedDB
-.
-open
-(
-dbname
-)
-;
-open
-.
-onerror
-=
-(
-)
-=
->
-{
-reject
-(
-open
-.
-error
-)
-;
-}
-;
-open
-.
-onupgradeneeded
-=
-(
-)
-=
->
-{
-const
-connection
-=
-open
-.
-result
-;
-connection
-.
-createObjectStore
-(
-'
-store
-'
-)
-;
-}
-;
-open
-.
-onsuccess
-=
-(
-)
-=
->
-{
-const
-connection
-=
-open
-.
-result
-;
-t
-.
-add_cleanup
-(
-(
-)
-=
->
-{
-connection
-.
-close
-(
-)
-;
-indexedDB
-.
-deleteDatabase
-(
-dbname
-)
-;
-}
-)
-;
-resolve
-(
-connection
-)
-;
-}
-;
-}
-)
-.
-then
-(
-connection
-=
->
-{
-db
-=
-connection
-;
-return
-navigator
-.
-storage
-.
-estimate
-(
-)
-;
-}
-)
-.
-then
-(
-estimate
-=
->
-{
-before
-=
-estimate
-.
-usage
-;
-return
-new
-Promise
-(
-(
-resolve
-reject
-)
-=
->
-{
-const
-tx
-=
-db
-.
-transaction
-(
-'
-store
-'
-'
-readwrite
-'
-)
-;
-tx
-.
-objectStore
-(
-'
-store
-'
-)
-.
-put
-(
-large_value
-'
-key
-'
-)
-;
-tx
-.
-onabort
-=
-(
-)
-=
->
-{
-reject
-(
-tx
-.
-error
-)
-;
-}
-;
-tx
-.
-oncomplete
-=
-(
-)
-=
->
-{
-resolve
-(
-)
-;
-}
-;
-}
-)
-;
-}
-)
-.
-then
-(
-(
-)
-=
->
-{
-return
-navigator
-.
-storage
-.
-estimate
-(
-)
-;
-}
-)
-.
-then
-(
-estimate
-=
->
-{
-after
-=
-estimate
-.
-usage
-;
-assert_greater_than
-(
-after
-before
-'
-estimated
-usage
-should
-increase
-'
-)
-;
-}
-)
-;
-}
-'
-estimate
-(
-)
-shows
-usage
-increase
-after
-1MB
-IndexedDB
-record
-is
-stored
-'
-)
-;