diff --git a/components/style/properties/longhand/margin.mako.rs b/components/style/properties/longhand/margin.mako.rs
index 1fe4e7cca615..5c8a62aa01f7 100644
--- a/components/style/properties/longhand/margin.mako.rs
+++ b/components/style/properties/longhand/margin.mako.rs
@@ -15,6 +15,7 @@
     ${helpers.predefined_type("margin-%s" % side[0], "LengthOrPercentageOrAuto",
                               "computed::LengthOrPercentageOrAuto::Length(Au(0))",
                               alias=maybe_moz_logical_alias(product, side, "-moz-margin-%s"),
+                              allow_quirks=not side[1],
                               animation_value_type="ComputedValue", logical = side[1], spec = spec,
                               allowed_in_page_rule=True)}
 % endfor
diff --git a/tests/wpt/metadata/quirks-mode/unitless-length.html.ini b/tests/wpt/metadata/quirks-mode/unitless-length.html.ini
index a584a4c7e625..3a7420644f1e 100644
--- a/tests/wpt/metadata/quirks-mode/unitless-length.html.ini
+++ b/tests/wpt/metadata/quirks-mode/unitless-length.html.ini
@@ -12,15 +12,6 @@
     expected:
       if os == "mac": FAIL
 
-  [margin-left: 1 (quirks)]
-    expected: FAIL
-
-  [margin-top: 1 (quirks)]
-    expected: FAIL
-
-  [margin-bottom: 1 (quirks)]
-    expected: FAIL
-
   [margin: 1 (quirks)]
     expected: FAIL
 
@@ -84,15 +75,6 @@
     expected:
       if os == "mac": FAIL
 
-  [margin-left: +1 (quirks)]
-    expected: FAIL
-
-  [margin-top: +1 (quirks)]
-    expected: FAIL
-
-  [margin-bottom: +1 (quirks)]
-    expected: FAIL
-
   [margin: +1 (quirks)]
     expected: FAIL
 
@@ -156,15 +138,6 @@
     expected:
       if os == "mac": FAIL
 
-  [margin-left: -1 (quirks)]
-    expected: FAIL
-
-  [margin-top: -1 (quirks)]
-    expected: FAIL
-
-  [margin-bottom: -1 (quirks)]
-    expected: FAIL
-
   [margin: -1 (quirks)]
     expected: FAIL
 
@@ -204,15 +177,6 @@
     expected:
       if os == "mac": FAIL
 
-  [margin-left: 1.5 (quirks)]
-    expected: FAIL
-
-  [margin-top: 1.5 (quirks)]
-    expected: FAIL
-
-  [margin-bottom: 1.5 (quirks)]
-    expected: FAIL
-
   [margin: 1.5 (quirks)]
     expected: FAIL
 
@@ -276,15 +240,6 @@
     expected:
       if os == "mac": FAIL
 
-  [margin-left: +1.5 (quirks)]
-    expected: FAIL
-
-  [margin-top: +1.5 (quirks)]
-    expected: FAIL
-
-  [margin-bottom: +1.5 (quirks)]
-    expected: FAIL
-
   [margin: +1.5 (quirks)]
     expected: FAIL
 
@@ -348,15 +303,6 @@
     expected:
       if os == "mac": FAIL
 
-  [margin-left: -1.5 (quirks)]
-    expected: FAIL
-
-  [margin-top: -1.5 (quirks)]
-    expected: FAIL
-
-  [margin-bottom: -1.5 (quirks)]
-    expected: FAIL
-
   [margin: -1.5 (quirks)]
     expected: FAIL