diff --git a/components/style/properties/shorthand/position.mako.rs b/components/style/properties/shorthand/position.mako.rs
index 94c3bee9ddc..b1d40e52a19 100644
--- a/components/style/properties/shorthand/position.mako.rs
+++ b/components/style/properties/shorthand/position.mako.rs
@@ -144,28 +144,6 @@
     use properties::longhands::align_content;
     use properties::longhands::justify_content;
 
-% if product == "servo":
-    impl From<align_content::SpecifiedValue> for justify_content::SpecifiedValue {
-        fn from(align: align_content::SpecifiedValue) ->
-            justify_content::SpecifiedValue {
-            match align {
-                align_content::SpecifiedValue::stretch =>
-                    justify_content::SpecifiedValue::stretch,
-                align_content::SpecifiedValue::flex_start =>
-                    justify_content::SpecifiedValue::flex_start,
-                align_content::SpecifiedValue::flex_end =>
-                    justify_content::SpecifiedValue::flex_end,
-                align_content::SpecifiedValue::center =>
-                    justify_content::SpecifiedValue::center,
-                align_content::SpecifiedValue::space_between =>
-                    justify_content::SpecifiedValue::space_between,
-                align_content::SpecifiedValue::space_around =>
-                    justify_content::SpecifiedValue::space_around,
-            }
-        }
-    }
-% endif
-
     pub fn parse_value(context: &ParserContext, input: &mut Parser) -> Result<Longhands, ()> {
         let align = align_content::parse(context, input)?;
         let justify = input.try(|input| justify_content::parse(context, input))
@@ -179,9 +157,13 @@
 
     impl<'a> ToCss for LonghandsToSerialize<'a> {
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            self.align_content.to_css(dest)?;
-            dest.write_str(" ")?;
-            self.justify_content.to_css(dest)
+            if self.align_content == self.justify_content {
+                self.align_content.to_css(dest)
+            } else {
+                self.justify_content.to_css(dest)?;
+                dest.write_str(" ")?;
+                self.justify_content.to_css(dest)
+            }
         }
     }
 </%helpers:shorthand>
@@ -204,9 +186,13 @@
 
     impl<'a> ToCss for LonghandsToSerialize<'a> {
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            self.align_self.to_css(dest)?;
-            dest.write_str(" ")?;
-            self.justify_self.to_css(dest)
+            if self.align_self == self.justify_self {
+                self.align_self.to_css(dest)
+            } else {
+                self.align_self.to_css(dest)?;
+                dest.write_str(" ")?;
+                self.justify_self.to_css(dest)
+            }
         }
     }
 </%helpers:shorthand>
@@ -236,9 +222,13 @@
 
     impl<'a> ToCss for LonghandsToSerialize<'a> {
         fn to_css<W>(&self, dest: &mut W) -> fmt::Result where W: fmt::Write {
-            self.align_items.to_css(dest)?;
-            dest.write_str(" ")?;
-            self.justify_items.to_css(dest)
+            if self.align_items.0 == self.justify_items.0 {
+                self.align_items.to_css(dest)
+            } else {
+                self.align_items.to_css(dest)?;
+                dest.write_str(" ")?;
+                self.justify_items.to_css(dest)
+            }
         }
     }
 </%helpers:shorthand>