diff --git a/components/style/gecko/pseudo_element.rs b/components/style/gecko/pseudo_element.rs
index dffd5acf086..defa6bec18d 100644
--- a/components/style/gecko/pseudo_element.rs
+++ b/components/style/gecko/pseudo_element.rs
@@ -186,6 +186,7 @@ impl PseudoElement {
             PseudoElement::FirstLetter => Some(PropertyFlags::APPLIES_TO_FIRST_LETTER),
             PseudoElement::FirstLine => Some(PropertyFlags::APPLIES_TO_FIRST_LINE),
             PseudoElement::Placeholder => Some(PropertyFlags::APPLIES_TO_PLACEHOLDER),
+            PseudoElement::Cue => Some(PropertyFlags::APPLIES_TO_CUE),
             _ => None,
         }
     }
diff --git a/components/style/properties/longhands/background.mako.rs b/components/style/properties/longhands/background.mako.rs
index e9e866983c0..cc416bc3af0 100644
--- a/components/style/properties/longhands/background.mako.rs
+++ b/components/style/properties/longhands/background.mako.rs
@@ -15,7 +15,7 @@ ${helpers.predefined_type(
     animation_value_type="AnimatedColor",
     ignored_when_colors_disabled=True,
     allow_quirks="Yes",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER \
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER \
            CAN_ANIMATE_ON_COMPOSITOR",
 )}
 
@@ -28,7 +28,7 @@ ${helpers.predefined_type(
     vector="True",
     animation_value_type="discrete",
     ignored_when_colors_disabled="True",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
 )}
 
 % for (axis, direction, initial) in [("x", "Horizontal", "left"), ("y", "Vertical", "top")]:
@@ -41,7 +41,7 @@ ${helpers.predefined_type(
         animation_value_type="ComputedValue",
         vector=True,
         vector_animation_type="repeatable_list",
-        flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+        flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     )}
 % endfor
 
@@ -53,7 +53,7 @@ ${helpers.predefined_type(
     animation_value_type="discrete",
     vector=True,
     spec="https://drafts.csswg.org/css-backgrounds/#the-background-repeat",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
 )}
 
 ${helpers.single_keyword(
@@ -63,7 +63,7 @@ ${helpers.single_keyword(
     gecko_enum_prefix="StyleImageLayerAttachment",
     spec="https://drafts.csswg.org/css-backgrounds/#the-background-attachment",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
 )}
 
 ${helpers.single_keyword(
@@ -75,7 +75,7 @@ ${helpers.single_keyword(
     gecko_inexhaustive=True,
     spec="https://drafts.csswg.org/css-backgrounds/#the-background-clip",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
 )}
 
 ${helpers.single_keyword(
@@ -86,7 +86,7 @@ ${helpers.single_keyword(
     gecko_inexhaustive=True,
     spec="https://drafts.csswg.org/css-backgrounds/#the-background-origin",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER"
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER"
 )}
 
 ${helpers.predefined_type(
@@ -98,7 +98,7 @@ ${helpers.predefined_type(
     vector=True,
     vector_animation_type="repeatable_list",
     animation_value_type="BackgroundSizeList",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     extra_prefixes="webkit")}
 
 // https://drafts.fxtf.org/compositing/#background-blend-mode
@@ -110,5 +110,5 @@ ${helpers.single_keyword(
     gecko_constant_prefix="NS_STYLE_BLEND",
     vector=True, products="gecko", animation_value_type="discrete",
     spec="https://drafts.fxtf.org/compositing/#background-blend-mode",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
 )}
diff --git a/components/style/properties/longhands/effects.mako.rs b/components/style/properties/longhands/effects.mako.rs
index c50a0d18ca6..34bd110c3c9 100644
--- a/components/style/properties/longhands/effects.mako.rs
+++ b/components/style/properties/longhands/effects.mako.rs
@@ -12,7 +12,7 @@ ${helpers.predefined_type(
     "Opacity",
     "1.0",
     animation_value_type="ComputedValue",
-    flags="CREATES_STACKING_CONTEXT APPLIES_TO_PLACEHOLDER \
+    flags="APPLIES_TO_CUE CREATES_STACKING_CONTEXT APPLIES_TO_PLACEHOLDER \
            CAN_ANIMATE_ON_COMPOSITOR",
     spec="https://drafts.csswg.org/css-color/#opacity",
     servo_restyle_damage = "reflow_out_of_flow",
diff --git a/components/style/properties/longhands/font.mako.rs b/components/style/properties/longhands/font.mako.rs
index 8d84ef34cb3..05682883804 100644
--- a/components/style/properties/longhands/font.mako.rs
+++ b/components/style/properties/longhands/font.mako.rs
@@ -12,7 +12,7 @@ ${helpers.predefined_type(
     "FontFamily",
     initial_value="computed::FontFamily::serif()",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-family",
     servo_restyle_damage="rebuild_and_reflow",
 )}
@@ -23,7 +23,7 @@ ${helpers.predefined_type(
     initial_value="computed::FontStyle::normal()",
     initial_specified_value="specified::FontStyle::normal()",
     animation_value_type="FontStyle",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-style",
     servo_restyle_damage="rebuild_and_reflow",
 )}
@@ -42,7 +42,7 @@ ${helpers.single_keyword_system(
     gecko_ffi_name="mFont.variantCaps",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-variant-caps",
     custom_consts=font_variant_caps_custom_consts,
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     animation_value_type="discrete",
     servo_restyle_damage="rebuild_and_reflow",
 )}
@@ -53,7 +53,7 @@ ${helpers.predefined_type(
     initial_value="computed::FontWeight::normal()",
     initial_specified_value="specified::FontWeight::normal()",
     animation_value_type="Number",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-weight",
     servo_restyle_damage="rebuild_and_reflow",
 )}
@@ -65,7 +65,7 @@ ${helpers.predefined_type(
     initial_specified_value="specified::FontSize::medium()",
     animation_value_type="NonNegativeLength",
     allow_quirks="Yes",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-size",
     servo_restyle_damage="rebuild_and_reflow",
 )}
@@ -77,7 +77,7 @@ ${helpers.predefined_type(
     initial_value="computed::FontSizeAdjust::none()",
     initial_specified_value="specified::FontSizeAdjust::none()",
     animation_value_type="ComputedValue",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-size-adjust",
 )}
 
@@ -87,7 +87,7 @@ ${helpers.predefined_type(
     products="gecko",
     initial_value="specified::FontSynthesis::get_initial_value()",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-synthesis",
 )}
 
@@ -97,7 +97,7 @@ ${helpers.predefined_type(
     initial_value="computed::FontStretch::hundred()",
     initial_specified_value="specified::FontStretch::normal()",
     animation_value_type="Percentage",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-stretch",
     servo_restyle_damage="rebuild_and_reflow",
 )}
@@ -109,7 +109,7 @@ ${helpers.single_keyword_system(
     gecko_ffi_name="mFont.kerning",
     gecko_constant_prefix="NS_FONT_KERNING",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-kerning",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     animation_value_type="discrete",
 )}
 
@@ -120,7 +120,7 @@ ${helpers.predefined_type(
     initial_value="computed::FontVariantAlternates::get_initial_value()",
     initial_specified_value="specified::FontVariantAlternates::get_initial_specified_value()",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-variant-alternates",
 )}
 
@@ -131,7 +131,7 @@ ${helpers.predefined_type(
     initial_value="computed::FontVariantEastAsian::empty()",
     initial_specified_value="specified::FontVariantEastAsian::empty()",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-variant-east-asian",
 )}
 
@@ -142,7 +142,7 @@ ${helpers.predefined_type(
     initial_value="computed::FontVariantLigatures::empty()",
     initial_specified_value="specified::FontVariantLigatures::empty()",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-variant-ligatures",
 )}
 
@@ -153,7 +153,7 @@ ${helpers.predefined_type(
     initial_value="computed::FontVariantNumeric::empty()",
     initial_specified_value="specified::FontVariantNumeric::empty()",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-variant-numeric",
 )}
 
@@ -164,7 +164,7 @@ ${helpers.single_keyword_system(
     gecko_ffi_name="mFont.variantPosition",
     gecko_constant_prefix="NS_FONT_VARIANT_POSITION",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-variant-position",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     animation_value_type="discrete",
 )}
 
@@ -176,7 +176,7 @@ ${helpers.predefined_type(
     initial_specified_value="specified::FontFeatureSettings::normal()",
     extra_prefixes="moz:layout.css.prefixes.font-features",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts/#propdef-font-feature-settings",
 )}
 
@@ -195,7 +195,7 @@ ${helpers.predefined_type(
     initial_value="computed::FontVariationSettings::normal()",
     initial_specified_value="specified::FontVariationSettings::normal()",
     animation_value_type="ComputedValue",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="${variation_spec}",
 )}
 
@@ -207,7 +207,7 @@ ${helpers.predefined_type(
     initial_specified_value="specified::FontLanguageOverride::normal()",
     animation_value_type="discrete",
     extra_prefixes="moz:layout.css.prefixes.font-features",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-fonts-3/#propdef-font-language-override",
 )}
 
@@ -219,7 +219,7 @@ ${helpers.single_keyword_system(
     gecko_ffi_name="mFont.opticalSizing",
     gecko_constant_prefix="NS_FONT_OPTICAL_SIZING",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://www.w3.org/TR/css-fonts-4/#font-optical-sizing-def",
 )}
 
@@ -514,7 +514,7 @@ ${helpers.single_keyword(
     gecko_pref="layout.css.osx-font-smoothing.enabled",
     products="gecko",
     spec="Nonstandard (https://developer.mozilla.org/en-US/docs/Web/CSS/font-smooth)",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     animation_value_type="discrete",
 )}
 
diff --git a/components/style/properties/longhands/inherited_box.mako.rs b/components/style/properties/longhands/inherited_box.mako.rs
index 0e3799f6c46..a7dee5dc03d 100644
--- a/components/style/properties/longhands/inherited_box.mako.rs
+++ b/components/style/properties/longhands/inherited_box.mako.rs
@@ -14,6 +14,7 @@ ${helpers.single_keyword(
     gecko_ffi_name="mVisible",
     animation_value_type="ComputedValue",
     spec="https://drafts.csswg.org/css-box/#propdef-visibility",
+    flags="APPLIES_TO_CUE",
 )}
 
 // CSS Writing Modes Level 3
diff --git a/components/style/properties/longhands/inherited_text.mako.rs b/components/style/properties/longhands/inherited_text.mako.rs
index fc934d901eb..7de8b5e20b1 100644
--- a/components/style/properties/longhands/inherited_text.mako.rs
+++ b/components/style/properties/longhands/inherited_text.mako.rs
@@ -11,7 +11,7 @@ ${helpers.predefined_type(
     "ColorPropertyValue",
     "::cssparser::RGBA::new(0, 0, 0, 255)",
     animation_value_type="AnimatedRGBA",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     ignored_when_colors_disabled="True",
     spec="https://drafts.csswg.org/css-color/#color",
 )}
@@ -21,7 +21,7 @@ ${helpers.predefined_type(
     "LineHeight",
     "computed::LineHeight::normal()",
     animation_value_type="LineHeight",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE \
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE \
            APPLIES_TO_PLACEHOLDER GETCS_NEEDS_LAYOUT_FLUSH",
     spec="https://drafts.csswg.org/css2/visudet.html#propdef-line-height",
     servo_restyle_damage="reflow"
@@ -181,7 +181,7 @@ ${helpers.predefined_type(
     needs_conversion="True"
     animation_value_type="discrete"
     // Only allowed for UA sheets, which set it !important.
-    flags="APPLIES_TO_PLACEHOLDER"
+    flags="APPLIES_TO_CUE APPLIES_TO_PLACEHOLDER"
     spec="https://drafts.csswg.org/css-text/#propdef-white-space"
     servo_restyle_damage="rebuild_and_reflow"
 >
@@ -229,7 +229,7 @@ ${helpers.predefined_type(
     animation_value_type="AnimatedTextShadowList",
     ignored_when_colors_disabled=True,
     simple_vector_bindings=True,
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-text-decor-3/#text-shadow-property",
 )}
 
@@ -337,6 +337,7 @@ ${helpers.single_keyword(
     products="gecko",
     animation_value_type="discrete",
     spec="https://drafts.csswg.org/css-ruby/#ruby-position-property",
+    flags="APPLIES_TO_CUE",
 )}
 
 // CSS Writing Modes Module Level 3
@@ -348,6 +349,7 @@ ${helpers.single_keyword(
     products="gecko",
     animation_value_type="discrete",
     spec="https://drafts.csswg.org/css-writing-modes-3/#text-combine-upright",
+    flags="APPLIES_TO_CUE",
 )}
 
 // SVG 1.1: Section 11 - Painting: Filling, Stroking and Marker Symbols
diff --git a/components/style/properties/longhands/outline.mako.rs b/components/style/properties/longhands/outline.mako.rs
index 8d0d326180b..ec765e631b8 100644
--- a/components/style/properties/longhands/outline.mako.rs
+++ b/components/style/properties/longhands/outline.mako.rs
@@ -18,6 +18,7 @@ ${helpers.predefined_type(
     animation_value_type="AnimatedColor",
     ignored_when_colors_disabled=True,
     spec="https://drafts.csswg.org/css-ui/#propdef-outline-color",
+    flags="APPLIES_TO_CUE",
 )}
 
 ${helpers.predefined_type(
@@ -27,6 +28,7 @@ ${helpers.predefined_type(
     initial_specified_value="specified::OutlineStyle::none()",
     animation_value_type="discrete",
     spec="https://drafts.csswg.org/css-ui/#propdef-outline-style",
+    flags="APPLIES_TO_CUE",
 )}
 
 ${helpers.predefined_type(
@@ -37,6 +39,7 @@ ${helpers.predefined_type(
     computed_type="crate::values::computed::NonNegativeLength",
     animation_value_type="NonNegativeLength",
     spec="https://drafts.csswg.org/css-ui/#propdef-outline-width",
+    flags="APPLIES_TO_CUE",
 )}
 
 // The -moz-outline-radius-* properties are non-standard and not on a standards track.
diff --git a/components/style/properties/longhands/text.mako.rs b/components/style/properties/longhands/text.mako.rs
index 91412d2ee6e..f7c77a16029 100644
--- a/components/style/properties/longhands/text.mako.rs
+++ b/components/style/properties/longhands/text.mako.rs
@@ -32,7 +32,7 @@ ${helpers.predefined_type(
     "specified::TextDecorationLine::none()",
     initial_specified_value="specified::TextDecorationLine::none()",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-text-decor/#propdef-text-decoration-line",
     servo_restyle_damage="rebuild_and_reflow",
 )}
@@ -42,7 +42,7 @@ ${helpers.single_keyword(
     "solid double dotted dashed wavy -moz-none",
     products="gecko",
     animation_value_type="discrete",
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-text-decor/#propdef-text-decoration-style",
 )}
 
@@ -54,7 +54,7 @@ ${helpers.predefined_type(
     products="gecko",
     animation_value_type="AnimatedColor",
     ignored_when_colors_disabled=True,
-    flags="APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
+    flags="APPLIES_TO_CUE APPLIES_TO_FIRST_LETTER APPLIES_TO_FIRST_LINE APPLIES_TO_PLACEHOLDER",
     spec="https://drafts.csswg.org/css-text-decor/#propdef-text-decoration-color",
 )}
 
diff --git a/components/style/properties/properties.mako.rs b/components/style/properties/properties.mako.rs
index c2b390c89d9..72a194b0c2c 100644
--- a/components/style/properties/properties.mako.rs
+++ b/components/style/properties/properties.mako.rs
@@ -939,7 +939,7 @@ impl CSSWideKeyword {
 
 bitflags! {
     /// A set of flags for properties.
-    pub struct PropertyFlags: u8 {
+    pub struct PropertyFlags: u16 {
         /// This property requires a stacking context.
         const CREATES_STACKING_CONTEXT = 1 << 0;
         /// This property has values that can establish a containing block for
@@ -954,13 +954,15 @@ bitflags! {
         const APPLIES_TO_FIRST_LINE = 1 << 4;
         /// This longhand property applies to ::placeholder.
         const APPLIES_TO_PLACEHOLDER = 1 << 5;
+        ///  This longhand property applies to ::cue.
+        const APPLIES_TO_CUE = 1 << 6;
         /// This property's getComputedStyle implementation requires layout
         /// to be flushed.
-        const GETCS_NEEDS_LAYOUT_FLUSH = 1 << 6;
+        const GETCS_NEEDS_LAYOUT_FLUSH = 1 << 7;
         /// This property is a legacy shorthand.
         ///
         /// https://drafts.csswg.org/css-cascade/#legacy-shorthand
-        const IS_LEGACY_SHORTHAND = 1 << 7;
+        const IS_LEGACY_SHORTHAND = 1 << 8;
 
         /* The following flags are currently not used in Rust code, they
          * only need to be listed in corresponding properties so that
@@ -1184,7 +1186,7 @@ impl LonghandId {
     pub fn flags(self) -> PropertyFlags {
         // TODO(emilio): This can be simplified further as Rust gains more
         // constant expression support.
-        const FLAGS: [u8; ${len(data.longhands)}] = [
+        const FLAGS: [u16; ${len(data.longhands)}] = [
             % for property in data.longhands:
                 % for flag in property.flags:
                     PropertyFlags::${flag}.bits |
@@ -1446,7 +1448,7 @@ impl ShorthandId {
     /// Returns PropertyFlags for the given shorthand property.
     #[inline]
     pub fn flags(self) -> PropertyFlags {
-        const FLAGS: [u8; ${len(data.shorthands)}] = [
+        const FLAGS: [u16; ${len(data.shorthands)}] = [
             % for property in data.shorthands:
                 % for flag in property.flags:
                     PropertyFlags::${flag}.bits |