diff --git a/components/style/properties/longhand/inherited_text.mako.rs b/components/style/properties/longhand/inherited_text.mako.rs
index 1ff10a50662..b24cdbbcacf 100644
--- a/components/style/properties/longhand/inherited_text.mako.rs
+++ b/components/style/properties/longhand/inherited_text.mako.rs
@@ -1076,6 +1076,28 @@ ${helpers.single_keyword("text-align-last",
             vertical.to_css(dest)
         }
     }
+
+    % if product == "gecko":
+        impl SpecifiedValue {
+            pub fn from_gecko_keyword(kw: u32) -> Self {
+                use gecko_bindings::structs;
+
+                let vert = if kw & structs::NS_STYLE_TEXT_EMPHASIS_POSITION_RIGHT != 0 {
+                    VerticalWritingModeValue::Right
+                } else {
+                    debug_assert!(kw & structs::NS_STYLE_TEXT_EMPHASIS_POSITION_LEFT != 0);
+                    VerticalWritingModeValue::Left
+                };
+                let horiz = if kw & structs::NS_STYLE_TEXT_EMPHASIS_POSITION_OVER != 0 {
+                    HorizontalWritingModeValue::Over
+                } else {
+                    debug_assert!(kw & structs::NS_STYLE_TEXT_EMPHASIS_POSITION_UNDER != 0);
+                    HorizontalWritingModeValue::Under
+                };
+                SpecifiedValue(horiz, vert)
+            }
+        }
+    % endif
 </%helpers:longhand>
 
 ${helpers.predefined_type("text-emphasis-color", "CSSColor",
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 1ce2e02b216..455aaaf41d2 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -1148,6 +1148,7 @@ pub extern "C" fn Servo_DeclarationBlock_SetKeywordValue(declarations:
         Float => longhands::float::SpecifiedValue::from_gecko_keyword(value),
         VerticalAlign => longhands::vertical_align::SpecifiedValue::from_gecko_keyword(value),
         TextAlign => longhands::text_align::SpecifiedValue::from_gecko_keyword(value),
+        TextEmphasisPosition => longhands::text_emphasis_position::SpecifiedValue::from_gecko_keyword(value),
         Clear => longhands::clear::SpecifiedValue::from_gecko_keyword(value),
         FontSize => {
             // We rely on Gecko passing in font-size values (0...7) here.