diff --git a/components/script/dom/htmlbuttonelement.rs b/components/script/dom/htmlbuttonelement.rs
index 75e8be38b17..25f90802c16 100644
--- a/components/script/dom/htmlbuttonelement.rs
+++ b/components/script/dom/htmlbuttonelement.rs
@@ -105,8 +105,14 @@ impl HTMLButtonElementMethods<crate::DomTypeHolder> for HTMLButtonElement {
         self.form_owner()
     }
 
-    // https://html.spec.whatwg.org/multipage/#dom-button-type
-    make_enumerated_getter!(Type, "type", "submit", "reset" | "button");
+    // <https://html.spec.whatwg.org/multipage/#dom-button-type>
+    make_enumerated_getter!(
+        Type,
+        "type",
+        "submit" | "reset" | "button",
+        missing => "submit",
+        invalid => "submit"
+    );
 
     // https://html.spec.whatwg.org/multipage/#dom-button-type
     make_setter!(SetType, "type");
@@ -121,15 +127,21 @@ impl HTMLButtonElementMethods<crate::DomTypeHolder> for HTMLButtonElement {
     make_enumerated_getter!(
         FormEnctype,
         "formenctype",
-        "application/x-www-form-urlencoded",
-        "text/plain" | "multipart/form-data"
+        "application/x-www-form-urlencoded" | "multipart/form-data" | "text/plain",
+        invalid => "application/x-www-form-urlencoded"
     );
 
     // https://html.spec.whatwg.org/multipage/#dom-fs-formenctype
     make_setter!(SetFormEnctype, "formenctype");
 
     // https://html.spec.whatwg.org/multipage/#dom-fs-formmethod
-    make_enumerated_getter!(FormMethod, "formmethod", "get", "post" | "dialog");
+    make_enumerated_getter!(
+        FormMethod,
+        "formmethod",
+        "get" | "post" | "dialog",
+        missing => "get",
+        invalid => "get"
+    );
 
     // https://html.spec.whatwg.org/multipage/#dom-fs-formmethod
     make_setter!(SetFormMethod, "formmethod");
diff --git a/components/script/dom/htmlelement.rs b/components/script/dom/htmlelement.rs
index 5f96e38851f..4917024fa2c 100644
--- a/components/script/dom/htmlelement.rs
+++ b/components/script/dom/htmlelement.rs
@@ -160,7 +160,14 @@ impl HTMLElementMethods<crate::DomTypeHolder> for HTMLElement {
     make_setter!(SetLang, "lang");
 
     // https://html.spec.whatwg.org/multipage/#the-dir-attribute
-    make_enumerated_getter!(Dir, "dir", "", "ltr" | "rtl" | "auto");
+    make_enumerated_getter!(
+        Dir,
+        "dir",
+        "ltr" | "rtl" | "auto",
+        missing => "",
+        invalid => ""
+    );
+
     // https://html.spec.whatwg.org/multipage/#the-dir-attribute
     make_setter!(SetDir, "dir");
 
diff --git a/components/script/dom/htmlformelement.rs b/components/script/dom/htmlformelement.rs
index 4fe3785d470..dd278cc8ad3 100644
--- a/components/script/dom/htmlformelement.rs
+++ b/components/script/dom/htmlformelement.rs
@@ -217,7 +217,13 @@ impl HTMLFormElementMethods<crate::DomTypeHolder> for HTMLFormElement {
     make_setter!(SetAction, "action");
 
     // https://html.spec.whatwg.org/multipage/#dom-form-autocomplete
-    make_enumerated_getter!(Autocomplete, "autocomplete", "on", "off");
+    make_enumerated_getter!(
+        Autocomplete,
+        "autocomplete",
+        "on" | "off",
+        missing => "on",
+        invalid => "on"
+    );
 
     // https://html.spec.whatwg.org/multipage/#dom-form-autocomplete
     make_setter!(SetAutocomplete, "autocomplete");
@@ -226,8 +232,9 @@ impl HTMLFormElementMethods<crate::DomTypeHolder> for HTMLFormElement {
     make_enumerated_getter!(
         Enctype,
         "enctype",
-        "application/x-www-form-urlencoded",
-        "text/plain" | "multipart/form-data"
+        "application/x-www-form-urlencoded" | "text/plain" | "multipart/form-data",
+        missing => "application/x-www-form-urlencoded",
+        invalid => "application/x-www-form-urlencoded"
     );
 
     // https://html.spec.whatwg.org/multipage/#dom-fs-enctype
@@ -244,7 +251,13 @@ impl HTMLFormElementMethods<crate::DomTypeHolder> for HTMLFormElement {
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-fs-method
-    make_enumerated_getter!(Method, "method", "get", "post" | "dialog");
+    make_enumerated_getter!(
+        Method,
+        "method",
+        "get" | "post" | "dialog",
+        missing => "get",
+        invalid => "get"
+    );
 
     // https://html.spec.whatwg.org/multipage/#dom-fs-method
     make_setter!(SetMethod, "method");
diff --git a/components/script/dom/htmlinputelement.rs b/components/script/dom/htmlinputelement.rs
index 5eae0866e1a..b2aaba04517 100644
--- a/components/script/dom/htmlinputelement.rs
+++ b/components/script/dom/htmlinputelement.rs
@@ -1399,21 +1399,28 @@ impl HTMLInputElementMethods<crate::DomTypeHolder> for HTMLInputElement {
     // https://html.spec.whatwg.org/multipage/#dom-input-formaction
     make_setter!(SetFormAction, "formaction");
 
-    // https://html.spec.whatwg.org/multipage/#dom-input-formenctype
+    // https://html.spec.whatwg.org/multipage/#dom-fs-formenctype
     make_enumerated_getter!(
         FormEnctype,
         "formenctype",
-        "application/x-www-form-urlencoded",
-        "text/plain" | "multipart/form-data"
+        "application/x-www-form-urlencoded" | "text/plain" | "multipart/form-data",
+        missing => "",
+        invalid => "application/x-www-form-urlencoded"
     );
 
     // https://html.spec.whatwg.org/multipage/#dom-input-formenctype
     make_setter!(SetFormEnctype, "formenctype");
 
-    // https://html.spec.whatwg.org/multipage/#dom-input-formmethod
-    make_enumerated_getter!(FormMethod, "formmethod", "get", "post" | "dialog");
+    // https://html.spec.whatwg.org/multipage/#dom-fs-formmethod
+    make_enumerated_getter!(
+        FormMethod,
+        "formmethod",
+        "get" | "post" | "dialog",
+        missing => "get",
+        invalid => "get"
+    );
 
-    // https://html.spec.whatwg.org/multipage/#dom-input-formmethod
+    // https://html.spec.whatwg.org/multipage/#dom-fs-formmethod
     make_setter!(SetFormMethod, "formmethod");
 
     // https://html.spec.whatwg.org/multipage/#dom-input-formtarget
diff --git a/components/script/dom/htmlmediaelement.rs b/components/script/dom/htmlmediaelement.rs
index b30fa3d4b22..7aeb765091f 100644
--- a/components/script/dom/htmlmediaelement.rs
+++ b/components/script/dom/htmlmediaelement.rs
@@ -2159,8 +2159,15 @@ impl HTMLMediaElementMethods<crate::DomTypeHolder> for HTMLMediaElement {
     }
 
     // https://html.spec.whatwg.org/multipage/#attr-media-preload
-    // Missing value default is user-agent defined.
-    make_enumerated_getter!(Preload, "preload", "", "none" | "metadata" | "auto");
+    // Missing/Invalid values are user-agent defined.
+    make_enumerated_getter!(
+        Preload,
+        "preload",
+        "none" | "metadata" | "auto",
+        missing => "auto",
+        invalid => "auto"
+    );
+
     // https://html.spec.whatwg.org/multipage/#attr-media-preload
     make_setter!(SetPreload, "preload");
 
diff --git a/components/script/dom/macros.rs b/components/script/dom/macros.rs
index f5268e72945..4d43656996c 100644
--- a/components/script/dom/macros.rs
+++ b/components/script/dom/macros.rs
@@ -158,22 +158,86 @@ macro_rules! make_labels_getter(
     );
 );
 
-#[macro_export]
+/// Implements the `To determine the state of an attribute` steps from
+/// <https://html.spec.whatwg.org/multipage/#keywords-and-enumerated-attributes>
 macro_rules! make_enumerated_getter(
-    ( $attr:ident, $htmlname:tt, $default:expr, $($choices:pat_param)|+) => (
+    ($attr:ident,
+        $htmlname:tt,
+        $($choices:literal)|+,
+        missing => $missing:literal,
+        invalid => $invalid:literal
+    ) => (
         fn $attr(&self) -> DOMString {
             use $crate::dom::bindings::inheritance::Castable;
             use $crate::dom::element::Element;
-            let element = self.upcast::<Element>();
-            let mut val = element.get_string_attribute(&html5ever::local_name!($htmlname));
-            val.make_ascii_lowercase();
-            // https://html.spec.whatwg.org/multipage/#attr-fs-method
-            match &*val {
-                $($choices)|+ => val,
-                _ => DOMString::from($default)
+            use $crate::dom::bindings::codegen::Bindings::AttrBinding::Attr_Binding::AttrMethods;
+
+            let attr_or_none = self.upcast::<Element>()
+                .get_attribute(&html5ever::ns!(), &html5ever::local_name!($htmlname));
+            match attr_or_none  {
+                // Step 1. If the attribute is not specified:
+                None => {
+                    // Step 1.1. If the attribute has a missing value default state defined, then return that
+                    // missing value default state.
+                    // Step 1.2 Otherwise, return no state.
+                    return DOMString::from($missing);
+                },
+                Some(attr) => {
+                    // Step 2. If the attribute's value is an ASCII case-insensitive match for one of the keywords
+                    // defined for the attribute, then return the state represented by that keyword.
+                    let value: DOMString = attr.Value().to_ascii_lowercase().into();
+                    $(
+                        if value.str() == $choices {
+                            return value;
+                        }
+                    )+
+
+                    // Step 3. If the attribute has an invalid value default state defined, then return that invalid
+                    // value default state.
+                    // Step 4. Return no state.
+                    return DOMString::from($invalid);
+                }
             }
         }
     );
+    ($attr:ident,
+        $htmlname:tt,
+        $($choices:literal)|+,
+    ) => (
+        make_enumerated_getter!(
+            $attr,
+            $htmlname,
+            $($choices)|+,
+            missing => "",
+            invalid => ""
+        );
+    );
+    ($attr:ident,
+        $htmlname:tt,
+        $($choices:literal)|+,
+        invalid => $invalid:literal
+    ) => (
+        make_enumerated_getter!(
+            $attr,
+            $htmlname,
+            $($choices)|+,
+            missing => "",
+            invalid => $invalid
+        );
+    );
+    ($attr:ident,
+        $htmlname:tt,
+        $($choices:literal)|+,
+        missing => $missing:literal,
+    ) => (
+        make_enumerated_getter!(
+            $attr,
+            $htmlname,
+            $($choices)|+,
+            missing => $missing,
+            invalid => ""
+        );
+    );
 );
 
 // concat_idents! doesn't work for function name positions, so
diff --git a/tests/wpt/meta/html/dom/reflection-forms-weekmonth.html.ini b/tests/wpt/meta/html/dom/reflection-forms-weekmonth.html.ini
index 748a792e7ee..c1f88030098 100644
--- a/tests/wpt/meta/html/dom/reflection-forms-weekmonth.html.ini
+++ b/tests/wpt/meta/html/dom/reflection-forms-weekmonth.html.ini
@@ -248,9 +248,6 @@
   [input.autocomplete: IDL set to object "test-valueOf"]
     expected: FAIL
 
-  [input.formEnctype: IDL get with DOM attribute unset]
-    expected: FAIL
-
   [input.formMethod: IDL get with DOM attribute unset]
     expected: FAIL
 
diff --git a/tests/wpt/meta/html/dom/reflection-forms.html.ini b/tests/wpt/meta/html/dom/reflection-forms.html.ini
index e216a11a0c0..dc44db86f7e 100644
--- a/tests/wpt/meta/html/dom/reflection-forms.html.ini
+++ b/tests/wpt/meta/html/dom/reflection-forms.html.ini
@@ -1130,9 +1130,6 @@
   [input.autocomplete: IDL set to object "test-valueOf"]
     expected: FAIL
 
-  [input.formEnctype: IDL get with DOM attribute unset]
-    expected: FAIL
-
   [input.formMethod: IDL get with DOM attribute unset]
     expected: FAIL
 
@@ -1604,9 +1601,6 @@
   [button.tabIndex: IDL set to -2147483648]
     expected: FAIL
 
-  [button.formEnctype: IDL get with DOM attribute unset]
-    expected: FAIL
-
   [button.formMethod: IDL get with DOM attribute unset]
     expected: FAIL