diff --git a/components/style/properties/longhand/inherited_text.mako.rs b/components/style/properties/longhand/inherited_text.mako.rs
index 07054fbbd56..d9fdfa20755 100644
--- a/components/style/properties/longhand/inherited_text.mako.rs
+++ b/components/style/properties/longhand/inherited_text.mako.rs
@@ -664,6 +664,7 @@ ${helpers.single_keyword("text-align-last",
 
 <%helpers:single_keyword_computed name="white-space"
                                   values="normal pre nowrap pre-wrap pre-line"
+                                  extra_gecko_values="-moz-pre-space"
                                   gecko_constant_prefix="NS_STYLE_WHITESPACE"
                                   needs_conversion="True"
                                   animation_type="none"
@@ -673,6 +674,7 @@ ${helpers.single_keyword("text-align-last",
     impl ComputedValueAsSpecified for SpecifiedValue {}
     no_viewport_percentage!(SpecifiedValue);
 
+    % if product != "gecko":
     impl SpecifiedValue {
         pub fn allow_wrap(&self) -> bool {
             match *self {
@@ -704,6 +706,7 @@ ${helpers.single_keyword("text-align-last",
             }
         }
     }
+    % endif
 </%helpers:single_keyword_computed>
 
 <%helpers:longhand name="text-shadow" animation_type="normal"