diff --git a/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/canvas-aspect-ratio.html b/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/canvas-aspect-ratio.html
new file mode 100644
index 0000000000000..1dd769eb3c257
--- /dev/null
+++ b/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/canvas-aspect-ratio.html
@@ -0,0 +1,253 @@
+<
+!
+doctype
+html
+>
+<
+title
+>
+Canvas
+width
+and
+height
+attributes
+are
+used
+to
+infer
+aspect
+-
+ratio
+<
+/
+title
+>
+<
+script
+src
+=
+"
+/
+resources
+/
+testharness
+.
+js
+"
+>
+<
+/
+script
+>
+<
+script
+src
+=
+"
+/
+resources
+/
+testharnessreport
+.
+js
+"
+>
+<
+/
+script
+>
+<
+style
+>
+canvas
+{
+width
+:
+100
+%
+;
+max
+-
+width
+:
+100px
+;
+height
+:
+auto
+;
+}
+<
+/
+style
+>
+<
+body
+>
+<
+script
+>
+let
+t
+=
+async_test
+(
+"
+Canvas
+width
+and
+height
+attributes
+are
+used
+to
+infer
+aspect
+-
+ratio
+"
+)
+;
+function
+assert_ratio
+(
+img
+expected
+)
+{
+let
+epsilon
+=
+0
+.
+001
+;
+assert_approx_equals
+(
+parseInt
+(
+getComputedStyle
+(
+img
+)
+.
+width
+10
+)
+/
+parseInt
+(
+getComputedStyle
+(
+img
+)
+.
+height
+10
+)
+expected
+epsilon
+)
+;
+}
+/
+/
+Create
+and
+append
+a
+new
+canvas
+and
+immediately
+check
+the
+ratio
+.
+t
+.
+step
+(
+function
+(
+)
+{
+var
+canvas
+=
+document
+.
+createElement
+(
+"
+canvas
+"
+)
+;
+canvas
+.
+setAttribute
+(
+"
+width
+"
+"
+250
+"
+)
+;
+canvas
+.
+setAttribute
+(
+"
+height
+"
+"
+100
+"
+)
+;
+document
+.
+body
+.
+appendChild
+(
+canvas
+)
+;
+/
+/
+Canvases
+always
+use
+the
+aspect
+ratio
+from
+their
+surface
+size
+.
+assert_ratio
+(
+canvas
+2
+.
+5
+)
+;
+t
+.
+done
+(
+)
+;
+}
+)
+;
+<
+/
+script
+>
diff --git a/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/img-aspect-ratio.tentative.html b/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/img-aspect-ratio.tentative.html
index b777dc68ebdbf..bea489a87871a 100644
--- a/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/img-aspect-ratio.tentative.html
+++ b/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/img-aspect-ratio.tentative.html
@@ -85,18 +85,6 @@
 img
 src
 =
-broken
-width
-=
-100
-height
-=
-125
->
-<
-img
-src
-=
 "
 /
 images
@@ -191,6 +179,264 @@
 )
 ;
 }
+/
+/
+Create
+and
+append
+a
+new
+image
+and
+immediately
+check
+the
+ratio
+.
+/
+/
+This
+is
+not
+racy
+because
+the
+spec
+requires
+the
+user
+agent
+to
+queue
+a
+task
+:
+/
+/
+https
+:
+/
+/
+html
+.
+spec
+.
+whatwg
+.
+org
+/
+multipage
+/
+images
+.
+html
+#
+updating
+-
+the
+-
+image
+-
+data
+t
+.
+step
+(
+function
+(
+)
+{
+var
+img
+=
+new
+Image
+(
+)
+;
+img
+.
+width
+=
+250
+;
+img
+.
+height
+=
+100
+;
+img
+.
+src
+=
+"
+/
+images
+/
+blue
+.
+png
+"
+;
+document
+.
+body
+.
+appendChild
+(
+img
+)
+;
+assert_ratio
+(
+img
+2
+.
+5
+)
+;
+img
+=
+new
+Image
+(
+)
+;
+img
+.
+setAttribute
+(
+"
+width
+"
+"
+0
+.
+8
+"
+)
+;
+img
+.
+setAttribute
+(
+"
+height
+"
+"
+0
+.
+2
+"
+)
+;
+img
+.
+src
+=
+"
+/
+images
+/
+blue
+.
+png
+"
+;
+document
+.
+body
+.
+appendChild
+(
+img
+)
+;
+assert_ratio
+(
+img
+4
+)
+;
+img
+=
+new
+Image
+(
+)
+;
+img
+.
+setAttribute
+(
+"
+width
+"
+"
+50
+%
+"
+)
+;
+img
+.
+setAttribute
+(
+"
+height
+"
+"
+25
+%
+"
+)
+;
+img
+.
+src
+=
+"
+/
+images
+/
+blue
+.
+png
+"
+;
+document
+.
+body
+.
+appendChild
+(
+img
+)
+;
+/
+/
+Percentages
+should
+be
+ignored
+.
+assert_equals
+(
+getComputedStyle
+(
+img
+)
+.
+height
+"
+0px
+"
+)
+;
+}
+)
+;
 onload
 =
 t
@@ -217,18 +463,32 @@
 (
 images
 [
-0
+2
 ]
-0
+1
 .
-8
+266
 )
 ;
+/
+/
+1
+.
+266
+is
+the
+original
+aspect
+ratio
+of
+blue
+.
+png
 assert_ratio
 (
 images
 [
-2
+1
 ]
 2
 .
@@ -253,7 +513,7 @@
 (
 images
 [
-1
+0
 ]
 2
 .
diff --git a/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/video-aspect-ratio.html b/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/video-aspect-ratio.html
new file mode 100644
index 0000000000000..f227c2f6c2380
--- /dev/null
+++ b/testing/web-platform/tests/html/rendering/replaced-elements/attributes-for-embedded-content-and-images/video-aspect-ratio.html
@@ -0,0 +1,388 @@
+<
+!
+doctype
+html
+>
+<
+title
+>
+Video
+width
+and
+height
+attributes
+are
+not
+used
+to
+infer
+aspect
+-
+ratio
+<
+/
+title
+>
+<
+script
+src
+=
+"
+/
+resources
+/
+testharness
+.
+js
+"
+>
+<
+/
+script
+>
+<
+script
+src
+=
+"
+/
+resources
+/
+testharnessreport
+.
+js
+"
+>
+<
+/
+script
+>
+<
+script
+src
+=
+"
+/
+common
+/
+media
+.
+js
+"
+>
+<
+/
+script
+>
+<
+style
+>
+video
+{
+width
+:
+100
+%
+;
+max
+-
+width
+:
+100px
+;
+height
+:
+auto
+;
+}
+<
+/
+style
+>
+<
+body
+>
+<
+script
+>
+let
+t
+=
+async_test
+(
+"
+Video
+width
+and
+height
+attributes
+are
+not
+used
+to
+infer
+aspect
+-
+ratio
+"
+)
+;
+function
+assert_ratio
+(
+img
+expected
+)
+{
+let
+epsilon
+=
+0
+.
+001
+;
+assert_approx_equals
+(
+parseInt
+(
+getComputedStyle
+(
+img
+)
+.
+width
+10
+)
+/
+parseInt
+(
+getComputedStyle
+(
+img
+)
+.
+height
+10
+)
+expected
+epsilon
+)
+;
+}
+/
+/
+Create
+and
+append
+a
+new
+video
+and
+immediately
+check
+the
+ratio
+.
+/
+/
+This
+is
+not
+racy
+because
+the
+spec
+requires
+the
+user
+agent
+to
+queue
+a
+task
+:
+/
+/
+https
+:
+/
+/
+html
+.
+spec
+.
+whatwg
+.
+org
+/
+multipage
+/
+media
+.
+html
+#
+concept
+-
+media
+-
+load
+-
+algorithm
+t
+.
+step
+(
+function
+(
+)
+{
+var
+video
+=
+document
+.
+createElement
+(
+"
+video
+"
+)
+;
+video
+.
+setAttribute
+(
+"
+width
+"
+"
+250
+"
+)
+;
+video
+.
+setAttribute
+(
+"
+height
+"
+"
+100
+"
+)
+;
+video
+.
+src
+=
+getVideoURI
+(
+'
+/
+media
+/
+2x2
+-
+green
+'
+)
+;
+document
+.
+body
+.
+appendChild
+(
+video
+)
+;
+/
+/
+Videos
+default
+to
+a
+size
+of
+300x150px
+and
+calculate
+their
+aspect
+ratio
+/
+/
+based
+on
+that
+before
+the
+video
+is
+loaded
+.
+So
+this
+should
+be
+2
+ignoring
+/
+/
+the
+2
+.
+5
+that
+it
+would
+be
+based
+on
+the
+attributes
+.
+assert_ratio
+(
+video
+2
+)
+;
+video
+.
+onloadeddata
+=
+t
+.
+step_func_done
+(
+function
+(
+)
+{
+/
+/
+When
+loaded
+this
+video
+is
+square
+.
+assert_ratio
+(
+video
+1
+)
+;
+}
+)
+;
+}
+)
+;
+<
+/
+script
+>