diff --git a/dom/canvas/CanvasRenderingContext2D.cpp b/dom/canvas/CanvasRenderingContext2D.cpp
index cd8ec8c41718..2d3f317c1f0b 100644
--- a/dom/canvas/CanvasRenderingContext2D.cpp
+++ b/dom/canvas/CanvasRenderingContext2D.cpp
@@ -2267,7 +2267,7 @@ static already_AddRefed<ComputedStyle> ResolveFilterStyleForServo(
 }
 
 bool CanvasRenderingContext2D::ParseFilter(
-    const nsAString& aString, nsTArray<nsStyleFilter>& aFilterChain,
+    const nsAString& aString, StyleOwnedSlice<StyleFilter>& aFilterChain,
     ErrorResult& aError) {
   if (!mCanvasElement && !mDocShell) {
     NS_WARNING(
@@ -2302,14 +2302,14 @@ bool CanvasRenderingContext2D::ParseFilter(
 
 void CanvasRenderingContext2D::SetFilter(const nsAString& aFilter,
                                          ErrorResult& aError) {
-  nsTArray<nsStyleFilter> filterChain;
+  StyleOwnedSlice<StyleFilter> filterChain;
   if (ParseFilter(aFilter, filterChain, aError)) {
     CurrentState().filterString = aFilter;
-    filterChain.SwapElements(CurrentState().filterChain);
+    CurrentState().filterChain = std::move(filterChain);
     if (mCanvasElement) {
       CurrentState().autoSVGFiltersObserver =
           SVGObserverUtils::ObserveFiltersForCanvasContext(
-              this, mCanvasElement, CurrentState().filterChain);
+              this, mCanvasElement, CurrentState().filterChain.AsSpan());
       UpdateFilter();
     }
   }
@@ -2376,7 +2376,8 @@ void CanvasRenderingContext2D::UpdateFilter() {
       (mCanvasElement && mCanvasElement->IsWriteOnly());
 
   CurrentState().filter = nsFilterInstance::GetFilterDescription(
-      mCanvasElement, CurrentState().filterChain, sourceGraphicIsTainted,
+      mCanvasElement, CurrentState().filterChain.AsSpan(),
+      sourceGraphicIsTainted,
       CanvasUserSpaceMetrics(
           GetSize(), CurrentState().fontFont, CurrentState().fontLanguage,
           CurrentState().fontExplicitLanguage, presShell->GetPresContext()),
diff --git a/dom/canvas/CanvasRenderingContext2D.h b/dom/canvas/CanvasRenderingContext2D.h
index eca324e8fe3a..9743e57017e2 100644
--- a/dom/canvas/CanvasRenderingContext2D.h
+++ b/dom/canvas/CanvasRenderingContext2D.h
@@ -566,7 +566,8 @@ class CanvasRenderingContext2D final : public nsICanvasRenderingContextInternal,
 
   // Returns whether a filter was successfully parsed.
   bool ParseFilter(const nsAString& aString,
-                   nsTArray<nsStyleFilter>& aFilterChain, ErrorResult& aError);
+                   StyleOwnedSlice<StyleFilter>& aFilterChain,
+                   ErrorResult& aError);
 
   // Returns whether the font was successfully updated.
   bool SetFontInternal(const nsAString& aFont, mozilla::ErrorResult& aError);
@@ -966,7 +967,7 @@ class CanvasRenderingContext2D final : public nsICanvasRenderingContextInternal,
     mozilla::gfx::JoinStyle lineJoin = mozilla::gfx::JoinStyle::MITER_OR_BEVEL;
 
     nsString filterString = nsString(u"none");
-    nsTArray<nsStyleFilter> filterChain;
+    StyleOwnedSlice<StyleFilter> filterChain;
     // RAII object that we obtain when we start to observer SVG filter elements
     // for rendering changes.  When released we stop observing the SVG elements.
     nsCOMPtr<nsISupports> autoSVGFiltersObserver;
diff --git a/layout/painting/nsDisplayList.cpp b/layout/painting/nsDisplayList.cpp
index 9e03060d34fc..1386e2e6b64f 100644
--- a/layout/painting/nsDisplayList.cpp
+++ b/layout/painting/nsDisplayList.cpp
@@ -9981,69 +9981,63 @@ static float ClampStdDeviation(float aStdDeviation) {
   return std::min(std::max(0.0f, aStdDeviation), 100.0f);
 }
 
-bool nsDisplayFilters::CreateWebRenderCSSFilters(WrFiltersHolder& wrFilters) {
+bool nsDisplayFilters::CreateWebRenderCSSFilters(WrFiltersHolder& aWrFilters) {
   // All CSS filters are supported by WebRender. SVG filters are not fully
   // supported, those use NS_STYLE_FILTER_URL and are handled separately.
-  const nsTArray<nsStyleFilter>& filters = mFrame->StyleEffects()->mFilters;
+  Span<const StyleFilter> filters = mFrame->StyleEffects()->mFilters.AsSpan();
 
   // If there are too many filters to render, then just pretend that we
   // succeeded, and don't render any of them.
   if (filters.Length() > StaticPrefs::WebRenderMaxFilterOpsPerChain()) {
     return true;
   }
-  wrFilters.filters.SetCapacity(filters.Length());
-
-  for (const nsStyleFilter& filter : filters) {
-    switch (filter.GetType()) {
-      case NS_STYLE_FILTER_BRIGHTNESS:
-        wrFilters.filters.AppendElement(wr::FilterOp::Brightness(
-            filter.GetFilterParameter().GetFactorOrPercentValue()));
+  aWrFilters.filters.SetCapacity(filters.Length());
+  auto& wrFilters = aWrFilters.filters;
+  for (const StyleFilter& filter : filters) {
+    switch (filter.tag) {
+      case StyleFilter::Tag::Brightness:
+        wrFilters.AppendElement(
+            wr::FilterOp::Brightness(filter.AsBrightness()));
         break;
-      case NS_STYLE_FILTER_CONTRAST:
-        wrFilters.filters.AppendElement(wr::FilterOp::Contrast(
-            filter.GetFilterParameter().GetFactorOrPercentValue()));
+      case StyleFilter::Tag::Contrast:
+        wrFilters.AppendElement(wr::FilterOp::Contrast(filter.AsContrast()));
         break;
-      case NS_STYLE_FILTER_GRAYSCALE:
-        wrFilters.filters.AppendElement(wr::FilterOp::Grayscale(
-            filter.GetFilterParameter().GetFactorOrPercentValue()));
+      case StyleFilter::Tag::Grayscale:
+        wrFilters.AppendElement(wr::FilterOp::Grayscale(filter.AsGrayscale()));
         break;
-      case NS_STYLE_FILTER_INVERT:
-        wrFilters.filters.AppendElement(wr::FilterOp::Invert(
-            filter.GetFilterParameter().GetFactorOrPercentValue()));
+      case StyleFilter::Tag::Invert:
+        wrFilters.AppendElement(wr::FilterOp::Invert(filter.AsInvert()));
         break;
-      case NS_STYLE_FILTER_OPACITY: {
-        float opacity = filter.GetFilterParameter().GetFactorOrPercentValue();
-        wrFilters.filters.AppendElement(wr::FilterOp::Opacity(
+      case StyleFilter::Tag::Opacity: {
+        float opacity = filter.AsOpacity();
+        wrFilters.AppendElement(wr::FilterOp::Opacity(
             wr::PropertyBinding<float>::Value(opacity), opacity));
         break;
       }
-      case NS_STYLE_FILTER_SATURATE:
-        wrFilters.filters.AppendElement(wr::FilterOp::Saturate(
-            filter.GetFilterParameter().GetFactorOrPercentValue()));
+      case StyleFilter::Tag::Saturate:
+        wrFilters.AppendElement(wr::FilterOp::Saturate(filter.AsSaturate()));
         break;
-      case NS_STYLE_FILTER_SEPIA: {
-        wrFilters.filters.AppendElement(wr::FilterOp::Sepia(
-            filter.GetFilterParameter().GetFactorOrPercentValue()));
+      case StyleFilter::Tag::Sepia:
+        wrFilters.AppendElement(wr::FilterOp::Sepia(filter.AsSepia()));
+        break;
+      case StyleFilter::Tag::HueRotate: {
+        wrFilters.AppendElement(
+            wr::FilterOp::HueRotate(filter.AsHueRotate().ToDegrees()));
         break;
       }
-      case NS_STYLE_FILTER_HUE_ROTATE: {
-        wrFilters.filters.AppendElement(wr::FilterOp::HueRotate(
-            (float)filter.GetFilterParameter().GetAngleValueInDegrees()));
-        break;
-      }
-      case NS_STYLE_FILTER_BLUR: {
+      case StyleFilter::Tag::Blur: {
+        // TODO(emilio): we should go directly from css pixels -> device pixels.
         float appUnitsPerDevPixel =
             mFrame->PresContext()->AppUnitsPerDevPixel();
-        wrFilters.filters.AppendElement(mozilla::wr::FilterOp::Blur(
+        wrFilters.AppendElement(mozilla::wr::FilterOp::Blur(
             ClampStdDeviation(NSAppUnitsToFloatPixels(
-                filter.GetFilterParameter().GetCoordValue(),
-                appUnitsPerDevPixel))));
+                filter.AsBlur().ToAppUnits(), appUnitsPerDevPixel))));
         break;
       }
-      case NS_STYLE_FILTER_DROP_SHADOW: {
+      case StyleFilter::Tag::DropShadow: {
         float appUnitsPerDevPixel =
             mFrame->PresContext()->AppUnitsPerDevPixel();
-        const StyleSimpleShadow& shadow = filter.GetDropShadow();
+        const StyleSimpleShadow& shadow = filter.AsDropShadow();
         nscolor color = shadow.color.CalcColor(mFrame);
 
         wr::Shadow wrShadow;
@@ -10056,9 +10050,7 @@ bool nsDisplayFilters::CreateWebRenderCSSFilters(WrFiltersHolder& wrFilters) {
                                                        appUnitsPerDevPixel);
         wrShadow.color = {NS_GET_R(color) / 255.0f, NS_GET_G(color) / 255.0f,
                           NS_GET_B(color) / 255.0f, NS_GET_A(color) / 255.0f};
-        auto filterOp = wr::FilterOp::DropShadow(wrShadow);
-
-        wrFilters.filters.AppendElement(filterOp);
+        wrFilters.AppendElement(wr::FilterOp::DropShadow(wrShadow));
         break;
       }
       default:
diff --git a/layout/style/GeckoBindings.cpp b/layout/style/GeckoBindings.cpp
index 35a822f44fe1..3e850c6bfa82 100644
--- a/layout/style/GeckoBindings.cpp
+++ b/layout/style/GeckoBindings.cpp
@@ -1551,20 +1551,6 @@ void Gecko_SetToSVGPath(StyleShapeSource* aShape,
   aShape->SetPath(MakeUnique<StyleSVGPath>(aCommands, aFill));
 }
 
-void Gecko_ResetFilters(nsStyleEffects* effects, size_t new_len) {
-  effects->mFilters.Clear();
-  effects->mFilters.SetLength(new_len);
-}
-
-void Gecko_CopyFiltersFrom(nsStyleEffects* aSrc, nsStyleEffects* aDest) {
-  aDest->mFilters = aSrc->mFilters;
-}
-
-void Gecko_nsStyleFilter_SetURLValue(nsStyleFilter* aEffects,
-                                     const StyleComputedUrl* aURL) {
-  aEffects->SetURL(*aURL);
-}
-
 void Gecko_nsStyleSVGPaint_CopyFrom(nsStyleSVGPaint* aDest,
                                     const nsStyleSVGPaint* aSrc) {
   *aDest = *aSrc;
diff --git a/layout/style/GeckoBindings.h b/layout/style/GeckoBindings.h
index 3181dbb3e1d4..c181cc4c62c1 100644
--- a/layout/style/GeckoBindings.h
+++ b/layout/style/GeckoBindings.h
@@ -536,9 +536,6 @@ void Gecko_ResetFilters(nsStyleEffects* effects, size_t new_len);
 
 void Gecko_CopyFiltersFrom(nsStyleEffects* aSrc, nsStyleEffects* aDest);
 
-void Gecko_nsStyleFilter_SetURLValue(nsStyleFilter* effects,
-                                     const mozilla::StyleComputedUrl* url);
-
 void Gecko_nsStyleSVGPaint_CopyFrom(nsStyleSVGPaint* dest,
                                     const nsStyleSVGPaint* src);
 
diff --git a/layout/style/ServoBindings.toml b/layout/style/ServoBindings.toml
index b235363815f3..af72c3e5a3b3 100644
--- a/layout/style/ServoBindings.toml
+++ b/layout/style/ServoBindings.toml
@@ -507,6 +507,7 @@ cbindgen-types = [
     { gecko = "StyleComputedUrl", servo = "gecko::url::ComputedUrl" },
     { gecko = "StyleComputedImageUrl", servo = "gecko::url::ComputedImageUrl" },
     { gecko = "StyleLoadData", servo = "gecko::url::LoadData" },
+    { gecko = "StyleGenericFilter", servo = "values::generics::effects::Filter" },
 ]
 
 mapped-generic-types = [
diff --git a/layout/style/ServoStyleConstsInlines.h b/layout/style/ServoStyleConstsInlines.h
index ad5c5b0df5b6..baa9ea110d7f 100644
--- a/layout/style/ServoStyleConstsInlines.h
+++ b/layout/style/ServoStyleConstsInlines.h
@@ -23,7 +23,21 @@
 namespace mozilla {
 
 template <typename T>
-inline StyleOwnedSlice<T>::StyleOwnedSlice(const StyleOwnedSlice& aOther) {
+inline void StyleOwnedSlice<T>::Clear() {
+  if (!len) {
+    return;
+  }
+  for (size_t i : IntegerRange(len)) {
+    ptr[i].~T();
+  }
+  free(ptr);
+  ptr = (T*)alignof(T);
+  len = 0;
+}
+
+template <typename T>
+inline void StyleOwnedSlice<T>::CopyFrom(const StyleOwnedSlice& aOther) {
+  Clear();
   len = aOther.len;
   if (!len) {
     ptr = (T*)alignof(T);
@@ -37,24 +51,36 @@ inline StyleOwnedSlice<T>::StyleOwnedSlice(const StyleOwnedSlice& aOther) {
 }
 
 template <typename T>
-inline StyleOwnedSlice<T>::StyleOwnedSlice(StyleOwnedSlice&& aOther) {
-  len = aOther.len;
-  ptr = aOther.ptr;
-  aOther.ptr = (T*)alignof(T);
-  aOther.len = 0;
+inline void StyleOwnedSlice<T>::SwapElements(StyleOwnedSlice& aOther) {
+  std::swap(ptr, aOther.ptr);
+  std::swap(len, aOther.len);
 }
 
 template <typename T>
-inline void StyleOwnedSlice<T>::Clear() {
-  if (!len) {
-    return;
-  }
-  for (size_t i : IntegerRange(len)) {
-    ptr[i].~T();
-  }
-  free(ptr);
-  ptr = (T*)alignof(T);
-  len = 0;
+inline StyleOwnedSlice<T>::StyleOwnedSlice(const StyleOwnedSlice& aOther)
+    : StyleOwnedSlice() {
+  CopyFrom(aOther);
+}
+
+template <typename T>
+inline StyleOwnedSlice<T>::StyleOwnedSlice(StyleOwnedSlice&& aOther)
+    : StyleOwnedSlice() {
+  SwapElements(aOther);
+}
+
+template <typename T>
+inline StyleOwnedSlice<T>& StyleOwnedSlice<T>::operator=(
+    const StyleOwnedSlice& aOther) {
+  CopyFrom(aOther);
+  return *this;
+}
+
+template <typename T>
+inline StyleOwnedSlice<T>& StyleOwnedSlice<T>::operator=(
+    StyleOwnedSlice&& aOther) {
+  Clear();
+  SwapElements(aOther);
+  return *this;
 }
 
 template <typename T>
diff --git a/layout/style/nsCSSProps.cpp b/layout/style/nsCSSProps.cpp
index f1fa7f588137..23dbe04f4c76 100644
--- a/layout/style/nsCSSProps.cpp
+++ b/layout/style/nsCSSProps.cpp
@@ -376,21 +376,6 @@ const KTableEntry nsCSSProps::kTextEmphasisStyleShapeKTable[] = {
     {eCSSKeyword_sesame, NS_STYLE_TEXT_EMPHASIS_STYLE_SESAME},
     {eCSSKeyword_UNKNOWN, -1}};
 
-// keyword tables for SVG properties
-
-const KTableEntry nsCSSProps::kFilterFunctionKTable[] = {
-    {eCSSKeyword_blur, NS_STYLE_FILTER_BLUR},
-    {eCSSKeyword_brightness, NS_STYLE_FILTER_BRIGHTNESS},
-    {eCSSKeyword_contrast, NS_STYLE_FILTER_CONTRAST},
-    {eCSSKeyword_grayscale, NS_STYLE_FILTER_GRAYSCALE},
-    {eCSSKeyword_invert, NS_STYLE_FILTER_INVERT},
-    {eCSSKeyword_opacity, NS_STYLE_FILTER_OPACITY},
-    {eCSSKeyword_saturate, NS_STYLE_FILTER_SATURATE},
-    {eCSSKeyword_sepia, NS_STYLE_FILTER_SEPIA},
-    {eCSSKeyword_hue_rotate, NS_STYLE_FILTER_HUE_ROTATE},
-    {eCSSKeyword_drop_shadow, NS_STYLE_FILTER_DROP_SHADOW},
-    {eCSSKeyword_UNKNOWN, -1}};
-
 int32_t nsCSSProps::FindIndexOfKeyword(nsCSSKeyword aKeyword,
                                        const KTableEntry aTable[]) {
   if (eCSSKeyword_UNKNOWN == aKeyword) {
diff --git a/layout/style/nsCSSProps.h b/layout/style/nsCSSProps.h
index 2410d90164d7..4eaa14920527 100644
--- a/layout/style/nsCSSProps.h
+++ b/layout/style/nsCSSProps.h
@@ -290,7 +290,6 @@ class nsCSSProps {
   // Not const because we modify its entries when the pref
   // "layout.css.background-clip.text" changes:
   static const KTableEntry kShapeRadiusKTable[];
-  static const KTableEntry kFilterFunctionKTable[];
   static const KTableEntry kBoxShadowTypeKTable[];
   static const KTableEntry kCursorKTable[];
   // Not const because we modify its entries when various
diff --git a/layout/style/nsComputedDOMStyle.h b/layout/style/nsComputedDOMStyle.h
index af777f21e80f..de3017ac4ba4 100644
--- a/layout/style/nsComputedDOMStyle.h
+++ b/layout/style/nsComputedDOMStyle.h
@@ -41,7 +41,6 @@ class nsDOMCSSValueList;
 struct nsMargin;
 class nsROCSSPrimitiveValue;
 class nsStyleCoord;
-struct nsStyleFilter;
 class nsStyleGradient;
 struct nsStyleImage;
 class nsStyleSides;
diff --git a/layout/style/nsStyleConsts.h b/layout/style/nsStyleConsts.h
index 3c70634556c6..f177447878b7 100644
--- a/layout/style/nsStyleConsts.h
+++ b/layout/style/nsStyleConsts.h
@@ -364,20 +364,6 @@ enum class StyleFlexDirection : uint8_t {
 // (rather than an internal numerical representation of some keyword).
 #define NS_STYLE_ORDER_INITIAL 0
 
-// See nsStyleFilter
-#define NS_STYLE_FILTER_NONE 0
-#define NS_STYLE_FILTER_URL 1
-#define NS_STYLE_FILTER_BLUR 2
-#define NS_STYLE_FILTER_BRIGHTNESS 3
-#define NS_STYLE_FILTER_CONTRAST 4
-#define NS_STYLE_FILTER_GRAYSCALE 5
-#define NS_STYLE_FILTER_INVERT 6
-#define NS_STYLE_FILTER_OPACITY 7
-#define NS_STYLE_FILTER_SATURATE 8
-#define NS_STYLE_FILTER_SEPIA 9
-#define NS_STYLE_FILTER_HUE_ROTATE 10
-#define NS_STYLE_FILTER_DROP_SHADOW 11
-
 // See nsStyleFont
 #define NS_STYLE_FONT_SIZE_XXSMALL 0
 #define NS_STYLE_FONT_SIZE_XSMALL 1
diff --git a/layout/style/nsStyleStruct.cpp b/layout/style/nsStyleStruct.cpp
index 48520645e030..eaed776e05be 100644
--- a/layout/style/nsStyleStruct.cpp
+++ b/layout/style/nsStyleStruct.cpp
@@ -1010,93 +1010,6 @@ void StyleShapeSource::DoDestroy() {
   mType = StyleShapeSourceType::None;
 }
 
-// --------------------
-// nsStyleFilter
-//
-nsStyleFilter::nsStyleFilter() : mType(NS_STYLE_FILTER_NONE) {
-  MOZ_COUNT_CTOR(nsStyleFilter);
-}
-
-nsStyleFilter::nsStyleFilter(const nsStyleFilter& aSource)
-    : mType(NS_STYLE_FILTER_NONE) {
-  MOZ_COUNT_CTOR(nsStyleFilter);
-  if (aSource.mType == NS_STYLE_FILTER_URL) {
-    SetURL(aSource.mURL);
-  } else if (aSource.mType == NS_STYLE_FILTER_DROP_SHADOW) {
-    SetDropShadow(aSource.mDropShadow);
-  } else if (aSource.mType != NS_STYLE_FILTER_NONE) {
-    SetFilterParameter(aSource.mFilterParameter, aSource.mType);
-  }
-}
-
-nsStyleFilter::~nsStyleFilter() {
-  ReleaseRef();
-  MOZ_COUNT_DTOR(nsStyleFilter);
-}
-
-nsStyleFilter& nsStyleFilter::operator=(const nsStyleFilter& aOther) {
-  if (this == &aOther) {
-    return *this;
-  }
-
-  if (aOther.mType == NS_STYLE_FILTER_URL) {
-    SetURL(aOther.mURL);
-  } else if (aOther.mType == NS_STYLE_FILTER_DROP_SHADOW) {
-    SetDropShadow(aOther.mDropShadow);
-  } else if (aOther.mType != NS_STYLE_FILTER_NONE) {
-    SetFilterParameter(aOther.mFilterParameter, aOther.mType);
-  } else {
-    ReleaseRef();
-    mType = NS_STYLE_FILTER_NONE;
-  }
-
-  return *this;
-}
-
-bool nsStyleFilter::operator==(const nsStyleFilter& aOther) const {
-  if (mType != aOther.mType) {
-    return false;
-  }
-
-  if (mType == NS_STYLE_FILTER_URL) {
-    return mURL == aOther.mURL;
-  } else if (mType == NS_STYLE_FILTER_DROP_SHADOW) {
-    return mDropShadow == aOther.mDropShadow;
-  } else if (mType != NS_STYLE_FILTER_NONE) {
-    return mFilterParameter == aOther.mFilterParameter;
-  }
-
-  return true;
-}
-
-void nsStyleFilter::ReleaseRef() {
-  if (mType == NS_STYLE_FILTER_DROP_SHADOW) {
-    mDropShadow.~StyleSimpleShadow();
-  } else if (mType == NS_STYLE_FILTER_URL) {
-    mURL.~StyleComputedUrl();
-  }
-}
-
-void nsStyleFilter::SetFilterParameter(const nsStyleCoord& aFilterParameter,
-                                       int32_t aType) {
-  ReleaseRef();
-  mFilterParameter = aFilterParameter;
-  mType = aType;
-}
-
-bool nsStyleFilter::SetURL(const StyleComputedUrl& aUrl) {
-  ReleaseRef();
-  new (&mURL) StyleComputedUrl(aUrl);
-  mType = NS_STYLE_FILTER_URL;
-  return true;
-}
-
-void nsStyleFilter::SetDropShadow(const StyleSimpleShadow& aSrc) {
-  ReleaseRef();
-  new (&mDropShadow) StyleSimpleShadow(aSrc);
-  mType = NS_STYLE_FILTER_DROP_SHADOW;
-}
-
 // --------------------
 // nsStyleSVGReset
 //
diff --git a/layout/style/nsStyleStruct.h b/layout/style/nsStyleStruct.h
index 2e068954844e..0a68b53f7bdf 100644
--- a/layout/style/nsStyleStruct.h
+++ b/layout/style/nsStyleStruct.h
@@ -2546,60 +2546,6 @@ struct MOZ_NEEDS_MEMMOVABLE_MEMBERS nsStyleSVG {
   uint8_t mContextFlags;
 };
 
-struct nsStyleFilter {
-  nsStyleFilter();
-  nsStyleFilter(const nsStyleFilter& aSource);
-  ~nsStyleFilter();
-  void TriggerImageLoads(mozilla::dom::Document&, const nsStyleFilter*) {}
-  const static bool kHasTriggerImageLoads = false;
-
-  nsStyleFilter& operator=(const nsStyleFilter& aOther);
-
-  bool operator==(const nsStyleFilter& aOther) const;
-  bool operator!=(const nsStyleFilter& aOther) const {
-    return !(*this == aOther);
-  }
-
-  uint32_t GetType() const { return mType; }
-
-  const nsStyleCoord& GetFilterParameter() const {
-    NS_ASSERTION(mType != NS_STYLE_FILTER_DROP_SHADOW &&
-                     mType != NS_STYLE_FILTER_URL &&
-                     mType != NS_STYLE_FILTER_NONE,
-                 "wrong filter type");
-    return mFilterParameter;
-  }
-  void SetFilterParameter(const nsStyleCoord& aFilterParameter, int32_t aType);
-
-  const mozilla::StyleComputedUrl& GetURL() const {
-    MOZ_ASSERT(mType == NS_STYLE_FILTER_URL, "wrong filter type");
-    return mURL;
-  }
-
-  bool SetURL(const mozilla::StyleComputedUrl& aUrl);
-
-  const mozilla::StyleSimpleShadow& GetDropShadow() const {
-    NS_ASSERTION(mType == NS_STYLE_FILTER_DROP_SHADOW, "wrong filter type");
-    return mDropShadow;
-  }
-  void SetDropShadow(const mozilla::StyleSimpleShadow&);
-
- private:
-  void ReleaseRef();
-
-  uint32_t mType;                 // NS_STYLE_FILTER_*
-  nsStyleCoord mFilterParameter;  // coord, percent, factor, angle
-  union {
-    mozilla::StyleComputedUrl mURL;
-    mozilla::StyleSimpleShadow mDropShadow;
-  };
-};
-
-template <>
-struct nsTArray_CopyChooser<nsStyleFilter> {
-  typedef nsTArray_CopyWithConstructors<nsStyleFilter> Type;
-};
-
 struct MOZ_NEEDS_MEMMOVABLE_MEMBERS nsStyleSVGReset {
   explicit nsStyleSVGReset(const mozilla::dom::Document&);
   nsStyleSVGReset(const nsStyleSVGReset& aSource);
@@ -2666,7 +2612,7 @@ struct MOZ_NEEDS_MEMMOVABLE_MEMBERS nsStyleEffects {
     return false;
   }
 
-  nsTArray<nsStyleFilter> mFilters;
+  mozilla::StyleOwnedSlice<mozilla::StyleFilter> mFilters;
   mozilla::StyleOwnedSlice<mozilla::StyleBoxShadow> mBoxShadow;
   nsRect mClip;  // offsets from UL border edge
   float mOpacity;
diff --git a/layout/svg/SVGObserverUtils.cpp b/layout/svg/SVGObserverUtils.cpp
index eb532c1553af..83d2bbe448a2 100644
--- a/layout/svg/SVGObserverUtils.cpp
+++ b/layout/svg/SVGObserverUtils.cpp
@@ -628,7 +628,7 @@ nsSVGFilterFrame* SVGFilterObserver::GetAndObserveFilterFrame() {
  */
 class SVGFilterObserverList : public nsISupports {
  public:
-  SVGFilterObserverList(const nsTArray<nsStyleFilter>& aFilters,
+  SVGFilterObserverList(Span<const StyleFilter> aFilters,
                         nsIContent* aFilteredElement,
                         nsIFrame* aFilteredFrame = nullptr);
 
@@ -684,25 +684,25 @@ NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(SVGFilterObserverList)
   NS_INTERFACE_MAP_ENTRY(nsISupports)
 NS_INTERFACE_MAP_END
 
-SVGFilterObserverList::SVGFilterObserverList(
-    const nsTArray<nsStyleFilter>& aFilters, nsIContent* aFilteredElement,
-    nsIFrame* aFilteredFrame) {
-  for (uint32_t i = 0; i < aFilters.Length(); i++) {
-    if (aFilters[i].GetType() != NS_STYLE_FILTER_URL) {
+SVGFilterObserverList::SVGFilterObserverList(Span<const StyleFilter> aFilters,
+                                             nsIContent* aFilteredElement,
+                                             nsIFrame* aFilteredFrame) {
+  for (const auto& filter : aFilters) {
+    if (!filter.IsUrl()) {
       continue;
     }
 
+    const auto& url = filter.AsUrl();
+
     // aFilteredFrame can be null if this filter belongs to a
     // CanvasRenderingContext2D.
     RefPtr<URLAndReferrerInfo> filterURL;
     if (aFilteredFrame) {
-      filterURL = ResolveURLUsingLocalRef(aFilteredFrame, aFilters[i].GetURL());
+      filterURL = ResolveURLUsingLocalRef(aFilteredFrame, url);
     } else {
-      nsCOMPtr<nsIURI> resolvedURI =
-          aFilters[i].GetURL().ResolveLocalRef(aFilteredElement);
+      nsCOMPtr<nsIURI> resolvedURI = url.ResolveLocalRef(aFilteredElement);
       if (resolvedURI) {
-        filterURL = new URLAndReferrerInfo(resolvedURI,
-                                           aFilters[i].GetURL().ExtraData());
+        filterURL = new URLAndReferrerInfo(resolvedURI, url.ExtraData());
       }
     }
 
@@ -725,7 +725,7 @@ bool SVGFilterObserverList::ReferencesValidResources() {
 
 class SVGFilterObserverListForCSSProp final : public SVGFilterObserverList {
  public:
-  SVGFilterObserverListForCSSProp(const nsTArray<nsStyleFilter>& aFilters,
+  SVGFilterObserverListForCSSProp(Span<const StyleFilter> aFilters,
                                   nsIFrame* aFilteredFrame)
       : SVGFilterObserverList(aFilters, aFilteredFrame->GetContent(),
                               aFilteredFrame),
@@ -769,7 +769,7 @@ class SVGFilterObserverListForCanvasContext final
  public:
   SVGFilterObserverListForCanvasContext(CanvasRenderingContext2D* aContext,
                                         Element* aCanvasElement,
-                                        nsTArray<nsStyleFilter>& aFilters)
+                                        Span<const StyleFilter> aFilters)
       : SVGFilterObserverList(aFilters, aCanvasElement), mContext(aContext) {}
 
   void OnRenderingChange() override;
@@ -1168,7 +1168,8 @@ static SVGFilterObserverListForCSSProp* GetOrCreateFilterObserverListForCSS(
     MOZ_ASSERT(observers, "this property should only store non-null values");
     return observers;
   }
-  observers = new SVGFilterObserverListForCSSProp(effects->mFilters, aFrame);
+  observers =
+      new SVGFilterObserverListForCSSProp(effects->mFilters.AsSpan(), aFrame);
   NS_ADDREF(observers);
   aFrame->AddProperty(FilterProperty(), observers);
   return observers;
@@ -1219,7 +1220,7 @@ SVGObserverUtils::ReferenceState SVGObserverUtils::GetFiltersIfObserving(
 
 already_AddRefed<nsISupports> SVGObserverUtils::ObserveFiltersForCanvasContext(
     CanvasRenderingContext2D* aContext, Element* aCanvasElement,
-    nsTArray<nsStyleFilter>& aFilters) {
+    const Span<const StyleFilter> aFilters) {
   return do_AddRef(new SVGFilterObserverListForCanvasContext(
       aContext, aCanvasElement, aFilters));
 }
@@ -1680,11 +1681,10 @@ already_AddRefed<nsIURI> SVGObserverUtils::GetBaseURLForLocalRef(
 }
 
 already_AddRefed<URLAndReferrerInfo> SVGObserverUtils::GetFilterURI(
-    nsIFrame* aFrame, const nsStyleFilter& aFilter) {
-  MOZ_ASSERT(aFrame->StyleEffects()->mFilters.Length());
-  MOZ_ASSERT(aFilter.GetType() == NS_STYLE_FILTER_URL);
-
-  return ResolveURLUsingLocalRef(aFrame, aFilter.GetURL());
+    nsIFrame* aFrame, const StyleFilter& aFilter) {
+  MOZ_ASSERT(!aFrame->StyleEffects()->mFilters.IsEmpty());
+  MOZ_ASSERT(aFilter.IsUrl());
+  return ResolveURLUsingLocalRef(aFrame, aFilter.AsUrl());
 }
 
 }  // namespace mozilla
diff --git a/layout/svg/SVGObserverUtils.h b/layout/svg/SVGObserverUtils.h
index a8e05f84954b..1391a9a71e50 100644
--- a/layout/svg/SVGObserverUtils.h
+++ b/layout/svg/SVGObserverUtils.h
@@ -296,13 +296,13 @@ class SVGObserverUtils {
    * set is destroyed or has its filter style reset).
    *
    * XXXjwatt: It's a bit unfortunate that both we and
-   * CanvasRenderingContext2D::UpdateFilter process the list of nsStyleFilter
+   * CanvasRenderingContext2D::UpdateFilter process the list of StyleFilter
    * objects separately.  It would be better to refactor things so that we only
    * do that work once.
    */
   static already_AddRefed<nsISupports> ObserveFiltersForCanvasContext(
       CanvasRenderingContext2D* aContext, Element* aCanvasElement,
-      nsTArray<nsStyleFilter>& aFilters);
+      Span<const StyleFilter> aFilters);
 
   /**
    * Called when cycle collecting CanvasRenderingContext2D, and requires the
@@ -403,7 +403,7 @@ class SVGObserverUtils {
    * A helper function to resolve filter URL.
    */
   static already_AddRefed<URLAndReferrerInfo> GetFilterURI(
-      nsIFrame* aFrame, const nsStyleFilter& aFilter);
+      nsIFrame* aFrame, const StyleFilter& aFilter);
 
   /**
    * Return a baseURL for resolving a local-ref URL.
diff --git a/layout/svg/nsCSSFilterInstance.cpp b/layout/svg/nsCSSFilterInstance.cpp
index 3260b4d9161a..7d7e56dc217e 100644
--- a/layout/svg/nsCSSFilterInstance.cpp
+++ b/layout/svg/nsCSSFilterInstance.cpp
@@ -30,7 +30,7 @@ static float ClampFactor(float aFactor) {
 }
 
 nsCSSFilterInstance::nsCSSFilterInstance(
-    const nsStyleFilter& aFilter, nscolor aShadowFallbackColor,
+    const StyleFilter& aFilter, nscolor aShadowFallbackColor,
     const nsIntRect& aTargetBoundsInFilterSpace,
     const gfxMatrix& aFrameSpaceInCSSPxToFilterSpaceTransform)
     : mFilter(aFilter),
@@ -45,35 +45,35 @@ nsresult nsCSSFilterInstance::BuildPrimitives(
   FilterPrimitiveDescription descr =
       CreatePrimitiveDescription(aPrimitiveDescrs, aInputIsTainted);
   nsresult result;
-  switch (mFilter.GetType()) {
-    case NS_STYLE_FILTER_BLUR:
+  switch (mFilter.tag) {
+    case StyleFilter::Tag::Blur:
       result = SetAttributesForBlur(descr);
       break;
-    case NS_STYLE_FILTER_BRIGHTNESS:
+    case StyleFilter::Tag::Brightness:
       result = SetAttributesForBrightness(descr);
       break;
-    case NS_STYLE_FILTER_CONTRAST:
+    case StyleFilter::Tag::Contrast:
       result = SetAttributesForContrast(descr);
       break;
-    case NS_STYLE_FILTER_DROP_SHADOW:
+    case StyleFilter::Tag::DropShadow:
       result = SetAttributesForDropShadow(descr);
       break;
-    case NS_STYLE_FILTER_GRAYSCALE:
+    case StyleFilter::Tag::Grayscale:
       result = SetAttributesForGrayscale(descr);
       break;
-    case NS_STYLE_FILTER_HUE_ROTATE:
+    case StyleFilter::Tag::HueRotate:
       result = SetAttributesForHueRotate(descr);
       break;
-    case NS_STYLE_FILTER_INVERT:
+    case StyleFilter::Tag::Invert:
       result = SetAttributesForInvert(descr);
       break;
-    case NS_STYLE_FILTER_OPACITY:
+    case StyleFilter::Tag::Opacity:
       result = SetAttributesForOpacity(descr);
       break;
-    case NS_STYLE_FILTER_SATURATE:
+    case StyleFilter::Tag::Saturate:
       result = SetAttributesForSaturate(descr);
       break;
-    case NS_STYLE_FILTER_SEPIA:
+    case StyleFilter::Tag::Sepia:
       result = SetAttributesForSepia(descr);
       break;
     default:
@@ -109,14 +109,9 @@ FilterPrimitiveDescription nsCSSFilterInstance::CreatePrimitiveDescription(
 
 nsresult nsCSSFilterInstance::SetAttributesForBlur(
     FilterPrimitiveDescription& aDescr) {
-  const nsStyleCoord& radiusInFrameSpace = mFilter.GetFilterParameter();
-  if (radiusInFrameSpace.GetUnit() != eStyleUnit_Coord) {
-    MOZ_ASSERT_UNREACHABLE("unexpected unit");
-    return NS_ERROR_FAILURE;
-  }
-
+  const Length& radiusInFrameSpace = mFilter.AsBlur();
   Size radiusInFilterSpace =
-      BlurRadiusToFilterSpace(radiusInFrameSpace.GetCoordValue());
+      BlurRadiusToFilterSpace(radiusInFrameSpace.ToAppUnits());
   GaussianBlurAttributes atts;
   atts.mStdDeviation = radiusInFilterSpace;
   aDescr.Attributes() = AsVariant(atts);
@@ -125,8 +120,7 @@ nsresult nsCSSFilterInstance::SetAttributesForBlur(
 
 nsresult nsCSSFilterInstance::SetAttributesForBrightness(
     FilterPrimitiveDescription& aDescr) {
-  const nsStyleCoord& styleValue = mFilter.GetFilterParameter();
-  float value = styleValue.GetFactorOrPercentValue();
+  float value = mFilter.AsBrightness();
   float intercept = 0.0f;
   ComponentTransferAttributes atts;
 
@@ -147,8 +141,7 @@ nsresult nsCSSFilterInstance::SetAttributesForBrightness(
 
 nsresult nsCSSFilterInstance::SetAttributesForContrast(
     FilterPrimitiveDescription& aDescr) {
-  const nsStyleCoord& styleValue = mFilter.GetFilterParameter();
-  float value = styleValue.GetFactorOrPercentValue();
+  float value = mFilter.AsContrast();
   float intercept = -(0.5 * value) + 0.5;
   ComponentTransferAttributes atts;
 
@@ -169,7 +162,7 @@ nsresult nsCSSFilterInstance::SetAttributesForContrast(
 
 nsresult nsCSSFilterInstance::SetAttributesForDropShadow(
     FilterPrimitiveDescription& aDescr) {
-  const auto& shadow = mFilter.GetDropShadow();
+  const auto& shadow = mFilter.AsDropShadow();
 
   DropShadowAttributes atts;
 
@@ -197,8 +190,7 @@ nsresult nsCSSFilterInstance::SetAttributesForGrayscale(
   atts.mType = (uint32_t)SVG_FECOLORMATRIX_TYPE_SATURATE;
 
   // Set color matrix values.
-  const nsStyleCoord& styleValue = mFilter.GetFilterParameter();
-  float value = 1 - ClampFactor(styleValue.GetFactorOrPercentValue());
+  float value = 1 - ClampFactor(mFilter.AsGrayscale());
   atts.mValues.AppendElements(&value, 1);
 
   aDescr.Attributes() = AsVariant(std::move(atts));
@@ -212,8 +204,7 @@ nsresult nsCSSFilterInstance::SetAttributesForHueRotate(
   atts.mType = (uint32_t)SVG_FECOLORMATRIX_TYPE_HUE_ROTATE;
 
   // Set color matrix values.
-  const nsStyleCoord& styleValue = mFilter.GetFilterParameter();
-  float value = styleValue.GetAngleValueInDegrees();
+  float value = mFilter.AsHueRotate().ToDegrees();
   atts.mValues.AppendElements(&value, 1);
 
   aDescr.Attributes() = AsVariant(std::move(atts));
@@ -223,8 +214,7 @@ nsresult nsCSSFilterInstance::SetAttributesForHueRotate(
 nsresult nsCSSFilterInstance::SetAttributesForInvert(
     FilterPrimitiveDescription& aDescr) {
   ComponentTransferAttributes atts;
-  const nsStyleCoord& styleValue = mFilter.GetFilterParameter();
-  float value = ClampFactor(styleValue.GetFactorOrPercentValue());
+  float value = ClampFactor(mFilter.AsInvert());
 
   // Set transfer functions for RGB.
   float invertTableValues[2];
@@ -246,8 +236,7 @@ nsresult nsCSSFilterInstance::SetAttributesForInvert(
 nsresult nsCSSFilterInstance::SetAttributesForOpacity(
     FilterPrimitiveDescription& aDescr) {
   OpacityAttributes atts;
-  const nsStyleCoord& styleValue = mFilter.GetFilterParameter();
-  float value = ClampFactor(styleValue.GetFactorOrPercentValue());
+  float value = ClampFactor(mFilter.AsOpacity());
 
   atts.mOpacity = value;
   aDescr.Attributes() = AsVariant(std::move(atts));
@@ -261,8 +250,7 @@ nsresult nsCSSFilterInstance::SetAttributesForSaturate(
   atts.mType = (uint32_t)SVG_FECOLORMATRIX_TYPE_SATURATE;
 
   // Set color matrix values.
-  const nsStyleCoord& styleValue = mFilter.GetFilterParameter();
-  float value = styleValue.GetFactorOrPercentValue();
+  float value = mFilter.AsSaturate();
   atts.mValues.AppendElements(&value, 1);
 
   aDescr.Attributes() = AsVariant(std::move(atts));
@@ -276,8 +264,7 @@ nsresult nsCSSFilterInstance::SetAttributesForSepia(
   atts.mType = (uint32_t)SVG_FECOLORMATRIX_TYPE_SEPIA;
 
   // Set color matrix values.
-  const nsStyleCoord& styleValue = mFilter.GetFilterParameter();
-  float value = ClampFactor(styleValue.GetFactorOrPercentValue());
+  float value = ClampFactor(mFilter.AsSepia());
   atts.mValues.AppendElements(&value, 1);
 
   aDescr.Attributes() = AsVariant(std::move(atts));
diff --git a/layout/svg/nsCSSFilterInstance.h b/layout/svg/nsCSSFilterInstance.h
index 6610eddc99fb..5db26f62d7d1 100644
--- a/layout/svg/nsCSSFilterInstance.h
+++ b/layout/svg/nsCSSFilterInstance.h
@@ -13,9 +13,7 @@
 #include "mozilla/gfx/Point.h"
 #include "mozilla/gfx/Types.h"
 #include "nsColor.h"
-#include "nsTArrayForwardDeclare.h"
-
-struct nsStyleFilter;
+#include "mozilla/ServoStyleConsts.h"
 
 /**
  * This class helps nsFilterInstance build its filter graph. It turns a CSS
@@ -23,6 +21,7 @@ struct nsStyleFilter;
  * FilterPrimitiveDescription connected to the filter graph.
  */
 class nsCSSFilterInstance {
+  using StyleFilter = mozilla::StyleFilter;
   typedef mozilla::gfx::Color Color;
   typedef mozilla::gfx::FilterPrimitiveDescription FilterPrimitiveDescription;
   typedef mozilla::gfx::IntPoint IntPoint;
@@ -41,7 +40,7 @@ class nsCSSFilterInstance {
    *   the filtered element's frame space in CSS pixels to filter space.
    */
   nsCSSFilterInstance(
-      const nsStyleFilter& aFilter, nscolor aShadowFallbackColor,
+      const StyleFilter& aFilter, nscolor aShadowFallbackColor,
       const nsIntRect& aTargetBoundsInFilterSpace,
       const gfxMatrix& aFrameSpaceInCSSPxToFilterSpaceTransform);
 
@@ -121,7 +120,7 @@ class nsCSSFilterInstance {
   /**
    * The CSS filter originally from the style system.
    */
-  const nsStyleFilter& mFilter;
+  const StyleFilter& mFilter;
 
   /**
    * The color that should be used for drop-shadow() filters that don't
diff --git a/layout/svg/nsFilterInstance.cpp b/layout/svg/nsFilterInstance.cpp
index 57401319a4db..3d895bb2ed73 100644
--- a/layout/svg/nsFilterInstance.cpp
+++ b/layout/svg/nsFilterInstance.cpp
@@ -35,7 +35,7 @@ using namespace mozilla::gfx;
 using namespace mozilla::image;
 
 FilterDescription nsFilterInstance::GetFilterDescription(
-    nsIContent* aFilteredElement, const nsTArray<nsStyleFilter>& aFilterChain,
+    nsIContent* aFilteredElement, Span<const StyleFilter> aFilterChain,
     bool aFilterInputIsTainted, const UserSpaceMetrics& aMetrics,
     const gfxRect& aBBox,
     nsTArray<RefPtr<SourceSurface>>& aOutAdditionalImages) {
@@ -61,7 +61,7 @@ void nsFilterInstance::PaintFilteredFrame(
     nsIFrame* aFilteredFrame, gfxContext* aCtx,
     nsSVGFilterPaintCallback* aPaintCallback, const nsRegion* aDirtyArea,
     imgDrawingParams& aImgParams, float aOpacity) {
-  auto& filterChain = aFilteredFrame->StyleEffects()->mFilters;
+  auto filterChain = aFilteredFrame->StyleEffects()->mFilters.AsSpan();
   UniquePtr<UserSpaceMetrics> metrics =
       UserSpaceMetricsForFrame(aFilteredFrame);
 
@@ -121,7 +121,7 @@ bool nsFilterInstance::BuildWebRenderFilters(nsIFrame* aFilteredFrame,
   aWrFilters.filter_datas.Clear();
   aWrFilters.values.Clear();
 
-  auto& filterChain = aFilteredFrame->StyleEffects()->mFilters;
+  auto filterChain = aFilteredFrame->StyleEffects()->mFilters.AsSpan();
   UniquePtr<UserSpaceMetrics> metrics =
       UserSpaceMetricsForFrame(aFilteredFrame);
 
@@ -375,7 +375,7 @@ nsRegion nsFilterInstance::GetPostFilterDirtyArea(
   }
 
   gfxMatrix tm = nsSVGUtils::GetCanvasTM(aFilteredFrame);
-  auto& filterChain = aFilteredFrame->StyleEffects()->mFilters;
+  auto filterChain = aFilteredFrame->StyleEffects()->mFilters.AsSpan();
   UniquePtr<UserSpaceMetrics> metrics =
       UserSpaceMetricsForFrame(aFilteredFrame);
   // Hardcode InputIsTainted to true because we don't want JS to be able to
@@ -396,7 +396,7 @@ nsRegion nsFilterInstance::GetPostFilterDirtyArea(
 nsRegion nsFilterInstance::GetPreFilterNeededArea(
     nsIFrame* aFilteredFrame, const nsRegion& aPostFilterDirtyRegion) {
   gfxMatrix tm = nsSVGUtils::GetCanvasTM(aFilteredFrame);
-  auto& filterChain = aFilteredFrame->StyleEffects()->mFilters;
+  auto filterChain = aFilteredFrame->StyleEffects()->mFilters.AsSpan();
   UniquePtr<UserSpaceMetrics> metrics =
       UserSpaceMetricsForFrame(aFilteredFrame);
   // Hardcode InputIsTainted to true because we don't want JS to be able to
@@ -428,7 +428,7 @@ nsRect nsFilterInstance::GetPostFilterBounds(nsIFrame* aFilteredFrame,
   }
 
   gfxMatrix tm = nsSVGUtils::GetCanvasTM(aFilteredFrame);
-  auto& filterChain = aFilteredFrame->StyleEffects()->mFilters;
+  auto filterChain = aFilteredFrame->StyleEffects()->mFilters.AsSpan();
   UniquePtr<UserSpaceMetrics> metrics =
       UserSpaceMetricsForFrame(aFilteredFrame);
   // Hardcode InputIsTainted to true because we don't want JS to be able to
@@ -446,10 +446,9 @@ nsRect nsFilterInstance::GetPostFilterBounds(nsIFrame* aFilteredFrame,
 
 nsFilterInstance::nsFilterInstance(
     nsIFrame* aTargetFrame, nsIContent* aTargetContent,
-    const UserSpaceMetrics& aMetrics,
-    const nsTArray<nsStyleFilter>& aFilterChain, bool aFilterInputIsTainted,
-    nsSVGFilterPaintCallback* aPaintCallback, const gfxMatrix& aPaintTransform,
-    const nsRegion* aPostFilterDirtyRegion,
+    const UserSpaceMetrics& aMetrics, Span<const StyleFilter> aFilterChain,
+    bool aFilterInputIsTainted, nsSVGFilterPaintCallback* aPaintCallback,
+    const gfxMatrix& aPaintTransform, const nsRegion* aPostFilterDirtyRegion,
     const nsRegion* aPreFilterDirtyRegion,
     const nsRect* aPreFilterVisualOverflowRectOverride,
     const gfxRect* aOverrideBBox)
@@ -555,9 +554,9 @@ gfxRect nsFilterInstance::FilterSpaceToUserSpace(
   return userSpaceRect;
 }
 
-nsresult nsFilterInstance::BuildPrimitives(
-    const nsTArray<nsStyleFilter>& aFilterChain, nsIFrame* aTargetFrame,
-    bool aFilterInputIsTainted) {
+nsresult nsFilterInstance::BuildPrimitives(Span<const StyleFilter> aFilterChain,
+                                           nsIFrame* aTargetFrame,
+                                           bool aFilterInputIsTainted) {
   nsTArray<FilterPrimitiveDescription> primitiveDescriptions;
 
   for (uint32_t i = 0; i < aFilterChain.Length(); i++) {
@@ -577,13 +576,13 @@ nsresult nsFilterInstance::BuildPrimitives(
 }
 
 nsresult nsFilterInstance::BuildPrimitivesForFilter(
-    const nsStyleFilter& aFilter, nsIFrame* aTargetFrame, bool aInputIsTainted,
+    const StyleFilter& aFilter, nsIFrame* aTargetFrame, bool aInputIsTainted,
     nsTArray<FilterPrimitiveDescription>& aPrimitiveDescriptions) {
   NS_ASSERTION(mUserSpaceToFilterSpaceScale.width > 0.0f &&
                    mFilterSpaceToUserSpaceScale.height > 0.0f,
                "scale factors between spaces should be positive values");
 
-  if (aFilter.GetType() == NS_STYLE_FILTER_URL) {
+  if (aFilter.IsUrl()) {
     // Build primitives for an SVG filter.
     nsSVGFilterInstance svgFilterInstance(aFilter, aTargetFrame, mTargetContent,
                                           mMetrics, mTargetBBox,
diff --git a/layout/svg/nsFilterInstance.h b/layout/svg/nsFilterInstance.h
index 5cfa3a4b8e46..4a717212ef2a 100644
--- a/layout/svg/nsFilterInstance.h
+++ b/layout/svg/nsFilterInstance.h
@@ -48,6 +48,10 @@ class UserSpaceMetrics;
  * http://www.w3.org/TR/SVG11/filters.html#FilterEffectsRegion
  */
 class nsFilterInstance {
+  template <typename T>
+  using Span = mozilla::Span<T>;
+  using StyleFilter = mozilla::StyleFilter;
+
   typedef mozilla::gfx::IntRect IntRect;
   typedef mozilla::gfx::SourceSurface SourceSurface;
   typedef mozilla::gfx::DrawTarget DrawTarget;
@@ -71,7 +75,7 @@ class nsFilterInstance {
    * @return A FilterDescription describing the filter.
    */
   static FilterDescription GetFilterDescription(
-      nsIContent* aFilteredElement, const nsTArray<nsStyleFilter>& aFilterChain,
+      nsIContent* aFilteredElement, Span<const StyleFilter> aFilterChain,
       bool aFilterInputIsTainted, const UserSpaceMetrics& aMetrics,
       const gfxRect& aBBox,
       nsTArray<RefPtr<SourceSurface>>& aOutAdditionalImages);
@@ -153,7 +157,7 @@ class nsFilterInstance {
    */
   nsFilterInstance(nsIFrame* aTargetFrame, nsIContent* aTargetContent,
                    const UserSpaceMetrics& aMetrics,
-                   const nsTArray<nsStyleFilter>& aFilterChain,
+                   Span<const StyleFilter> aFilterChain,
                    bool aFilterInputIsTainted,
                    nsSVGFilterPaintCallback* aPaintCallback,
                    const gfxMatrix& aPaintTransform,
@@ -251,7 +255,7 @@ class nsFilterInstance {
    * mPrimitiveDescriptions and mInputImages. aFilterInputIsTainted describes
    * whether the SourceGraphic is tainted.
    */
-  nsresult BuildPrimitives(const nsTArray<nsStyleFilter>& aFilterChain,
+  nsresult BuildPrimitives(Span<const StyleFilter> aFilterChain,
                            nsIFrame* aTargetFrame, bool aFilterInputIsTainted);
 
   /**
@@ -261,8 +265,7 @@ class nsFilterInstance {
    * tainted.
    */
   nsresult BuildPrimitivesForFilter(
-      const nsStyleFilter& aFilter, nsIFrame* aTargetFrame,
-      bool aInputIsTainted,
+      const StyleFilter& aFilter, nsIFrame* aTargetFrame, bool aInputIsTainted,
       nsTArray<FilterPrimitiveDescription>& aPrimitiveDescriptions);
 
   /**
diff --git a/layout/svg/nsSVGFilterInstance.cpp b/layout/svg/nsSVGFilterInstance.cpp
index 1aa0c64edf46..6fd3acda3aa0 100644
--- a/layout/svg/nsSVGFilterInstance.cpp
+++ b/layout/svg/nsSVGFilterInstance.cpp
@@ -29,7 +29,7 @@ using namespace mozilla::dom::SVGUnitTypes_Binding;
 using namespace mozilla::gfx;
 
 nsSVGFilterInstance::nsSVGFilterInstance(
-    const nsStyleFilter& aFilter, nsIFrame* aTargetFrame,
+    const StyleFilter& aFilter, nsIFrame* aTargetFrame,
     nsIContent* aTargetContent, const UserSpaceMetrics& aMetrics,
     const gfxRect& aTargetBBox, const gfxSize& aUserSpaceToFilterSpaceScale)
     : mFilter(aFilter),
@@ -109,7 +109,7 @@ bool nsSVGFilterInstance::ComputeBounds() {
 }
 
 nsSVGFilterFrame* nsSVGFilterInstance::GetFilterFrame(nsIFrame* aTargetFrame) {
-  if (mFilter.GetType() != NS_STYLE_FILTER_URL) {
+  if (!mFilter.IsUrl()) {
     // The filter is not an SVG reference filter.
     return nullptr;
   }
@@ -134,12 +134,12 @@ nsSVGFilterFrame* nsSVGFilterInstance::GetFilterFrame(nsIFrame* aTargetFrame) {
 
     url = urlExtraReferrer->GetURI();
   } else {
-    url = mFilter.GetURL().ResolveLocalRef(mTargetContent);
+    url = mFilter.AsUrl().ResolveLocalRef(mTargetContent);
   }
 
   if (!url) {
     MOZ_ASSERT_UNREACHABLE(
-        "an nsStyleFilter of type URL should have a non-null URL");
+        "an StyleFilter of type URL should have a non-null URL");
     return nullptr;
   }
 
@@ -147,8 +147,8 @@ nsSVGFilterFrame* nsSVGFilterInstance::GetFilterFrame(nsIFrame* aTargetFrame) {
   IDTracker idTracker;
   bool watch = false;
   idTracker.ResetToURIFragmentID(
-      mTargetContent, url, mFilter.GetURL().ExtraData().GetReferrer(),
-      mFilter.GetURL().ExtraData().GetReferrerPolicy(), watch);
+      mTargetContent, url, mFilter.AsUrl().ExtraData().GetReferrer(),
+      mFilter.AsUrl().ExtraData().GetReferrerPolicy(), watch);
   Element* element = idTracker.get();
   if (!element) {
     // The URL points to no element.
diff --git a/layout/svg/nsSVGFilterInstance.h b/layout/svg/nsSVGFilterInstance.h
index 72f4c34fb39d..fd04234f5660 100644
--- a/layout/svg/nsSVGFilterInstance.h
+++ b/layout/svg/nsSVGFilterInstance.h
@@ -12,10 +12,9 @@
 #include "SVGAnimatedNumber.h"
 #include "SVGAnimatedNumberPair.h"
 #include "SVGFilters.h"
-#include "nsTArray.h"
+#include "mozilla/ServoStyleConsts.h"
 
 class nsSVGFilterFrame;
-struct nsStyleFilter;
 
 namespace mozilla {
 namespace dom {
@@ -65,6 +64,7 @@ class SVGFilterElement;
  *   "filter space point" = (20, 20)
  */
 class nsSVGFilterInstance {
+  using StyleFilter = mozilla::StyleFilter;
   typedef mozilla::SVGAnimatedNumber SVGAnimatedNumber;
   typedef mozilla::SVGAnimatedNumberPair SVGAnimatedNumberPair;
   typedef mozilla::gfx::Point3D Point3D;
@@ -83,7 +83,7 @@ class nsSVGFilterInstance {
    * @param aTargetBBox The SVG bbox to use for the target frame, computed by
    *   the caller. The caller may decide to override the actual SVG bbox.
    */
-  nsSVGFilterInstance(const nsStyleFilter& aFilter, nsIFrame* aTargetFrame,
+  nsSVGFilterInstance(const StyleFilter& aFilter, nsIFrame* aTargetFrame,
                       nsIContent* aTargetContent,
                       const UserSpaceMetrics& aMetrics,
                       const gfxRect& aTargetBBox,
@@ -202,7 +202,7 @@ class nsSVGFilterInstance {
   /**
    * The SVG reference filter originally from the style system.
    */
-  const nsStyleFilter& mFilter;
+  const StyleFilter& mFilter;
 
   /**
    * The filtered element.
diff --git a/servo/components/style/gecko/url.rs b/servo/components/style/gecko/url.rs
index 8435895b8959..4f1efdf052cc 100644
--- a/servo/components/style/gecko/url.rs
+++ b/servo/components/style/gecko/url.rs
@@ -256,7 +256,6 @@ impl ToComputedValue for SpecifiedUrl {
 
 /// A specified image `url()` value.
 #[derive(Clone, Debug, Eq, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToCss, ToShmem)]
-#[repr(C)]
 pub struct SpecifiedImageUrl(pub SpecifiedUrl);
 
 impl SpecifiedImageUrl {
@@ -340,6 +339,7 @@ impl ToCss for ComputedUrl {
 
 /// The computed value of a CSS image `url()`.
 #[derive(Clone, Debug, Eq, MallocSizeOf, PartialEq)]
+#[repr(transparent)]
 pub struct ComputedImageUrl(pub ComputedUrl);
 
 impl ComputedImageUrl {
diff --git a/servo/components/style/properties/gecko.mako.rs b/servo/components/style/properties/gecko.mako.rs
index 45e3124c8582..e5595673cb71 100644
--- a/servo/components/style/properties/gecko.mako.rs
+++ b/servo/components/style/properties/gecko.mako.rs
@@ -33,13 +33,11 @@ use crate::gecko_bindings::bindings::Gecko_nsStyleFont_CopyLangFrom;
 use crate::gecko_bindings::bindings::Gecko_SetListStyleImageNone;
 use crate::gecko_bindings::bindings::Gecko_SetListStyleImageImageValue;
 use crate::gecko_bindings::bindings::Gecko_SetNullImageValue;
-use crate::gecko_bindings::bindings::{Gecko_ResetFilters, Gecko_CopyFiltersFrom};
 use crate::gecko_bindings::structs;
 use crate::gecko_bindings::structs::nsCSSPropertyID;
 use crate::gecko_bindings::structs::mozilla::PseudoStyleType;
-use crate::gecko_bindings::sugar::ns_style_coord::{CoordDataValue, CoordDataMut};
+use crate::gecko_bindings::sugar::ns_style_coord::CoordDataMut;
 use crate::gecko_bindings::sugar::refptr::RefPtr;
-use crate::gecko::values::GeckoStyleCoordConvertible;
 use crate::gecko::values::round_border_to_device_pixels;
 use crate::logical_geometry::WritingMode;
 use crate::media_queries::Device;
@@ -52,11 +50,10 @@ use std::marker::PhantomData;
 use std::mem::{forget, uninitialized, zeroed, ManuallyDrop};
 use std::{cmp, ops, ptr};
 use crate::values::{self, CustomIdent, Either, KeyframesName, None_};
-use crate::values::computed::{NonNegativeLength, Percentage, TransitionProperty};
+use crate::values::computed::{Percentage, TransitionProperty};
 use crate::values::computed::url::ComputedImageUrl;
 use crate::values::computed::BorderStyle;
 use crate::values::computed::font::FontSize;
-use crate::values::computed::effects::Filter;
 use crate::values::generics::column::ColumnCount;
 use crate::values::generics::transform::TransformStyle;
 use crate::values::generics::url::UrlOrNone;
@@ -2162,6 +2159,7 @@ fn static_assert() {
         gecko_inexhaustive=True,
     ) %>
     ${impl_keyword('clear', 'mBreakType', clear_keyword)}
+
     ${impl_transition_time_value('delay', 'Delay')}
     ${impl_transition_time_value('duration', 'Duration')}
     ${impl_transition_timing_function()}
@@ -2926,8 +2924,7 @@ fn static_assert() {
     ${impl_simple_copy('_x_span', 'mSpan')}
 </%self:impl_trait>
 
-<%self:impl_trait style_struct_name="Effects"
-                  skip_longhands="clip filter">
+<%self:impl_trait style_struct_name="Effects" skip_longhands="clip">
     pub fn set_clip(&mut self, v: longhands::clip::computed_value::T) {
         use crate::gecko_bindings::structs::NS_STYLE_CLIP_AUTO;
         use crate::gecko_bindings::structs::NS_STYLE_CLIP_RECT;
@@ -3035,136 +3032,6 @@ fn static_assert() {
 
         Either::First(ClipRect { top, right, bottom, left })
     }
-
-    <%
-    # This array is several filter function which has percentage or
-    # number value for function of clone / set.
-    # The setting / cloning process of other function(e.g. Blur / HueRotate) is
-    # different from these function. So this array don't include such function.
-    FILTER_FUNCTIONS = [ 'Brightness', 'Contrast', 'Grayscale', 'Invert',
-                         'Opacity', 'Saturate', 'Sepia' ]
-     %>
-
-    pub fn set_filter<I>(&mut self, v: I)
-    where
-        I: IntoIterator<Item = Filter>,
-        I::IntoIter: ExactSizeIterator,
-    {
-        use crate::values::generics::effects::Filter::*;
-        use crate::gecko_bindings::structs::nsStyleFilter;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_BLUR;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_BRIGHTNESS;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_CONTRAST;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_GRAYSCALE;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_INVERT;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_OPACITY;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_SATURATE;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_SEPIA;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_HUE_ROTATE;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_DROP_SHADOW;
-
-        fn fill_filter(m_type: u32, value: CoordDataValue, gecko_filter: &mut nsStyleFilter){
-            gecko_filter.mType = m_type;
-            gecko_filter.mFilterParameter.set_value(value);
-        }
-
-        let v = v.into_iter();
-        unsafe {
-            Gecko_ResetFilters(&mut *self.gecko, v.len());
-        }
-        debug_assert_eq!(v.len(), self.gecko.mFilters.len());
-
-        for (servo, gecko_filter) in v.zip(self.gecko.mFilters.iter_mut()) {
-            match servo {
-                % for func in FILTER_FUNCTIONS:
-                ${func}(factor) => fill_filter(NS_STYLE_FILTER_${func.upper()},
-                                               CoordDataValue::Factor(factor.0),
-                                               gecko_filter),
-                % endfor
-                Blur(length) => fill_filter(NS_STYLE_FILTER_BLUR,
-                                            CoordDataValue::Coord(length.0.to_i32_au()),
-                                            gecko_filter),
-
-                HueRotate(angle) => fill_filter(NS_STYLE_FILTER_HUE_ROTATE,
-                                                CoordDataValue::from(angle),
-                                                gecko_filter),
-
-                DropShadow(shadow) => {
-                    gecko_filter.mType = NS_STYLE_FILTER_DROP_SHADOW;
-                    unsafe {
-                        let ref mut union = gecko_filter.__bindgen_anon_1;
-                        ptr::write(union.mDropShadow.as_mut(), shadow);
-                    }
-                },
-                Url(ref url) => {
-                    unsafe {
-                        bindings::Gecko_nsStyleFilter_SetURLValue(gecko_filter, url);
-                    }
-                },
-            }
-        }
-    }
-
-    pub fn copy_filter_from(&mut self, other: &Self) {
-        unsafe {
-            Gecko_CopyFiltersFrom(&other.gecko as *const _ as *mut _, &mut *self.gecko);
-        }
-    }
-
-    pub fn reset_filter(&mut self, other: &Self) {
-        self.copy_filter_from(other)
-    }
-
-    pub fn clone_filter(&self) -> longhands::filter::computed_value::T {
-        use crate::values::generics::effects::Filter;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_BLUR;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_BRIGHTNESS;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_CONTRAST;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_GRAYSCALE;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_INVERT;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_OPACITY;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_SATURATE;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_SEPIA;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_HUE_ROTATE;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_DROP_SHADOW;
-        use crate::gecko_bindings::structs::NS_STYLE_FILTER_URL;
-
-        longhands::filter::computed_value::List(self.gecko.mFilters.iter().map(|filter| {
-            match filter.mType {
-                % for func in FILTER_FUNCTIONS:
-                NS_STYLE_FILTER_${func.upper()} => {
-                    Filter::${func}(
-                        GeckoStyleCoordConvertible::from_gecko_style_coord(
-                            &filter.mFilterParameter
-                        ).unwrap()
-                    )
-                },
-                % endfor
-                NS_STYLE_FILTER_BLUR => {
-                    Filter::Blur(NonNegativeLength::from_gecko_style_coord(
-                        &filter.mFilterParameter
-                    ).unwrap())
-                },
-                NS_STYLE_FILTER_HUE_ROTATE => {
-                    Filter::HueRotate(GeckoStyleCoordConvertible::from_gecko_style_coord(
-                        &filter.mFilterParameter,
-                    ).unwrap())
-                },
-                NS_STYLE_FILTER_DROP_SHADOW => {
-                    Filter::DropShadow(unsafe {
-                        (*filter.__bindgen_anon_1.mDropShadow.as_ref()).clone()
-                    })
-                },
-                NS_STYLE_FILTER_URL => {
-                    Filter::Url(unsafe {
-                        filter.__bindgen_anon_1.mURL.as_ref().clone()
-                    })
-                }
-                _ => unreachable!("Unknown filter function?"),
-            }
-        }).collect())
-    }
-
 </%self:impl_trait>
 
 <%self:impl_trait style_struct_name="InheritedBox">
diff --git a/servo/components/style/properties/helpers/animated_properties.mako.rs b/servo/components/style/properties/helpers/animated_properties.mako.rs
index d3b3ecd11e40..48f499c7ec3a 100644
--- a/servo/components/style/properties/helpers/animated_properties.mako.rs
+++ b/servo/components/style/properties/helpers/animated_properties.mako.rs
@@ -22,7 +22,7 @@ use std::mem::{self, ManuallyDrop};
 use crate::hash::FxHashMap;
 use super::ComputedValues;
 use crate::values::animated::{Animate, Procedure, ToAnimatedValue, ToAnimatedZero};
-use crate::values::animated::effects::Filter as AnimatedFilter;
+use crate::values::animated::effects::AnimatedFilter;
 #[cfg(feature = "gecko")] use crate::values::computed::TransitionProperty;
 use crate::values::computed::{ClipRect, Context};
 use crate::values::computed::ToComputedValue;
diff --git a/servo/components/style/properties/longhands/effects.mako.rs b/servo/components/style/properties/longhands/effects.mako.rs
index 9bb8adda32eb..c50a0d18ca63 100644
--- a/servo/components/style/properties/longhands/effects.mako.rs
+++ b/servo/components/style/properties/longhands/effects.mako.rs
@@ -47,6 +47,8 @@ ${helpers.predefined_type(
     "Filter",
     None,
     vector=True,
+    simple_vector_bindings=True,
+    gecko_ffi_name="mFilters",
     separator="Space",
     animation_value_type="AnimatedFilterList",
     vector_animation_type="with_zero",
diff --git a/servo/components/style/values/animated/effects.rs b/servo/components/style/values/animated/effects.rs
index 4c559cd4c30d..49e751fec555 100644
--- a/servo/components/style/values/animated/effects.rs
+++ b/servo/components/style/values/animated/effects.rs
@@ -19,8 +19,8 @@ pub type AnimatedSimpleShadow = GenericSimpleShadow<Color, Length, Length>;
 
 /// An animated value for a single `filter`.
 #[cfg(feature = "gecko")]
-pub type Filter = GenericFilter<Angle, Number, Length, AnimatedSimpleShadow, ComputedUrl>;
+pub type AnimatedFilter = GenericFilter<Angle, Number, Length, AnimatedSimpleShadow, ComputedUrl>;
 
 /// An animated value for a single `filter`.
 #[cfg(not(feature = "gecko"))]
-pub type Filter = GenericFilter<Angle, Number, Length, Impossible, Impossible>;
+pub type AnimatedFilter = GenericFilter<Angle, Number, Length, Impossible, Impossible>;
diff --git a/servo/components/style/values/computed/effects.rs b/servo/components/style/values/computed/effects.rs
index d103f407a75c..24ec689e49c2 100644
--- a/servo/components/style/values/computed/effects.rs
+++ b/servo/components/style/values/computed/effects.rs
@@ -24,7 +24,7 @@ pub type Filter =
     GenericFilter<Angle, NonNegativeNumber, NonNegativeLength, SimpleShadow, ComputedUrl>;
 
 /// A computed value for a single `filter`.
-#[cfg(not(feature = "gecko"))]
+#[cfg(feature = "servo")]
 pub type Filter =
     GenericFilter<Angle, NonNegativeNumber, NonNegativeLength, Impossible, Impossible>;
 
diff --git a/servo/components/style/values/generics/effects.rs b/servo/components/style/values/generics/effects.rs
index a27adc49e524..beca716e9970 100644
--- a/servo/components/style/values/generics/effects.rs
+++ b/servo/components/style/values/generics/effects.rs
@@ -34,8 +34,10 @@ pub struct GenericBoxShadow<Color, SizeLength, BlurShapeLength, ShapeLength> {
 pub use self::GenericBoxShadow as BoxShadow;
 
 /// A generic value for a single `filter`.
+///
+/// cbindgen:derive-tagged-enum-copy-constructor=true
 #[cfg_attr(feature = "servo", derive(Deserialize, Serialize))]
-#[animation(no_bound(Url))]
+#[animation(no_bound(U))]
 #[derive(
     Clone,
     ComputeSquaredDistance,
@@ -49,7 +51,8 @@ pub use self::GenericBoxShadow as BoxShadow;
     ToResolvedValue,
     ToShmem,
 )]
-pub enum Filter<Angle, Factor, Length, DropShadow, Url> {
+#[repr(C, u8)]
+pub enum GenericFilter<Angle, Factor, Length, Shadow, U> {
     /// `blur(<length>)`
     #[css(function)]
     Blur(Length),
@@ -79,12 +82,14 @@ pub enum Filter<Angle, Factor, Length, DropShadow, Url> {
     Sepia(Factor),
     /// `drop-shadow(...)`
     #[css(function)]
-    DropShadow(DropShadow),
+    DropShadow(Shadow),
     /// `<url>`
     #[animation(error)]
-    Url(Url),
+    Url(U),
 }
 
+pub use self::GenericFilter as Filter;
+
 /// A generic value for the `drop-shadow()` filter and the `text-shadow` property.
 ///
 /// Contrary to the canonical order from the spec, the color is serialised
diff --git a/servo/components/style/values/specified/effects.rs b/servo/components/style/values/specified/effects.rs
index 3ffad2fa89cd..24af52d15564 100644
--- a/servo/components/style/values/specified/effects.rs
+++ b/servo/components/style/values/specified/effects.rs
@@ -18,7 +18,7 @@ use crate::values::specified::length::{Length, NonNegativeLength};
 #[cfg(feature = "gecko")]
 use crate::values::specified::url::SpecifiedUrl;
 use crate::values::specified::{Angle, Number, NumberOrPercentage};
-#[cfg(not(feature = "gecko"))]
+#[cfg(feature = "servo")]
 use crate::values::Impossible;
 use crate::Zero;
 use cssparser::{self, BasicParseErrorKind, Parser, Token};
@@ -30,11 +30,13 @@ pub type BoxShadow =
 
 /// A specified value for a single `filter`.
 #[cfg(feature = "gecko")]
-pub type Filter = GenericFilter<Angle, Factor, NonNegativeLength, SimpleShadow, SpecifiedUrl>;
+pub type SpecifiedFilter = GenericFilter<Angle, Factor, NonNegativeLength, SimpleShadow, SpecifiedUrl>;
 
 /// A specified value for a single `filter`.
-#[cfg(not(feature = "gecko"))]
-pub type Filter = GenericFilter<Angle, Factor, NonNegativeLength, Impossible, Impossible>;
+#[cfg(feature = "servo")]
+pub type SpecifiedFilter = GenericFilter<Angle, Factor, NonNegativeLength, Impossible, Impossible>;
+
+pub use self::SpecifiedFilter as Filter;
 
 /// A value for the `<factor>` parts in `Filter`.
 #[derive(Clone, Debug, MallocSizeOf, PartialEq, SpecifiedValueInfo, ToCss, ToShmem)]
diff --git a/servo/ports/geckolib/cbindgen.toml b/servo/ports/geckolib/cbindgen.toml
index 9e99fb7f3851..3ed6f2d4d3b5 100644
--- a/servo/ports/geckolib/cbindgen.toml
+++ b/servo/ports/geckolib/cbindgen.toml
@@ -35,6 +35,11 @@ include = ["style", "cssparser", "style_traits", "servo_arc"]
 derive_eq = true
 derive_neq = true
 
+[defines]
+# This will actually never be defined, but is handy to avoid cbindgen
+# generating Servo-only types.
+"feature = servo" = "CBINDGEN_IS_SERVO"
+
 [macro_expansion]
 bitflags = true
 
@@ -143,6 +148,7 @@ include = [
   "ComputedUrl",
   "ComputedImageUrl",
   "UrlOrNone",
+  "Filter",
 ]
 item_types = ["enums", "structs", "typedefs", "functions"]
 renaming_overrides_prefixing = true
@@ -364,15 +370,16 @@ renaming_overrides_prefixing = true
     ptr((T*)alignof(T)),
     len(0) {}
 
-  // Should be easily implementable if wanted, but the default implementation would leak.
-  StyleOwnedSlice& operator=(const StyleOwnedSlice&) = delete;
-  StyleOwnedSlice& operator=(StyleOwnedSlice&&) = delete;
+  inline void Clear();
+  inline void CopyFrom(const StyleOwnedSlice&);
+  inline void SwapElements(StyleOwnedSlice&);
+
+  StyleOwnedSlice& operator=(const StyleOwnedSlice&);
+  StyleOwnedSlice& operator=(StyleOwnedSlice&&);
 
   inline StyleOwnedSlice(const StyleOwnedSlice&);
   inline StyleOwnedSlice(StyleOwnedSlice&&);
 
-  inline void Clear();
-
   inline ~StyleOwnedSlice();
 
   Span<const T> AsSpan() const {
@@ -457,6 +464,9 @@ renaming_overrides_prefixing = true
   inline bool IsStatic() const;
   inline nsAtom* AsAtom() const;
 
+  // Could be implemented if wanted.
+  StyleAtom& operator=(const StyleAtom&) = delete;
+
   inline StyleAtom(const StyleAtom& aOther);
   inline ~StyleAtom();
 """