diff --git a/render-wasm/src/render/svg/snapshots/render_wasm__render__svg__tests__exports_leaf_inner_shadow_as_svg_filter.snap b/render-wasm/src/render/svg/snapshots/render_wasm__render__svg__tests__exports_leaf_inner_shadow_as_svg_filter.snap
index feb3c531dd..1127c671f0 100644
--- a/render-wasm/src/render/svg/snapshots/render_wasm__render__svg__tests__exports_leaf_inner_shadow_as_svg_filter.snap
+++ b/render-wasm/src/render/svg/snapshots/render_wasm__render__svg__tests__exports_leaf_inner_shadow_as_svg_filter.snap
@@ -3,6 +3,6 @@ source: src/render/svg/tests.rs
 expression: svg
 ---
 <?xml version="1.0" encoding="utf-8" ?>
-<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="123.78461" height="103.78461" viewBox="0 0 123.78461 103.78461"><defs><filter id="fx0" filterUnits="userSpaceOnUse" x="0" y="0" width="123.78461" height="103.78461" color-interpolation-filters="sRGB"><feFlood flood-opacity="0" result="bg"/><feBlend mode="normal" in="SourceGraphic" in2="bg" result="shape"/><feColorMatrix in="SourceAlpha" type="matrix" values="0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 127 0" result="hardAlpha"/><feOffset in="hardAlpha" dx="2" dy="3" result="off"/><feGaussianBlur in="off" stdDeviation="3.9641016" result="blurred"/><feComposite in="blurred" in2="hardAlpha" operator="arithmetic" k2="-1" k3="1" result="shadow"/><feColorMatrix in="shadow" type="matrix" values="0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.7058824 0" result="colored"/><feBlend mode="normal" in="colored" in2="shape" result="inner0"/></filter></defs><g filter="url(#fx0)">
-	<rect fill="#0080FF" transform="translate(9.8923 8.8923)" width="100" height="80"/>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" width="100" height="80" viewBox="0 0 100 80"><defs><filter id="fx0" filterUnits="userSpaceOnUse" x="0" y="0" width="100" height="80" color-interpolation-filters="sRGB"><feFlood flood-opacity="0" result="bg"/><feBlend mode="normal" in="SourceGraphic" in2="bg" result="shape"/><feColorMatrix in="SourceAlpha" type="matrix" values="0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 127 0" result="hardAlpha"/><feOffset in="hardAlpha" dx="2" dy="3" result="off"/><feGaussianBlur in="off" stdDeviation="3.9641016" result="blurred"/><feComposite in="blurred" in2="hardAlpha" operator="arithmetic" k2="-1" k3="1" result="shadow"/><feColorMatrix in="shadow" type="matrix" values="0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.7058824 0" result="colored"/><feBlend mode="normal" in="colored" in2="shape" result="inner0"/></filter></defs><g filter="url(#fx0)">
+	<rect fill="#0080FF" width="100" height="80"/>
 </g></svg>
diff --git a/render-wasm/src/shapes.rs b/render-wasm/src/shapes.rs
index e766b723d3..aaf4e55a49 100644
--- a/render-wasm/src/shapes.rs
+++ b/render-wasm/src/shapes.rs
@@ -1005,16 +1005,14 @@ impl Shape {
         let max_stroke = Stroke::max_bounds_width(self.strokes.iter(), self.is_open());
 
         let mut rect = bounds.to_rect();
-        for shadow in self.shadows_visible() {
-            if !shadow.hidden() {
-                if let Some(filter) = shadow.get_drop_shadow_filter() {
-                    let mut source = rect;
-                    if mitered && shadow.spread > 0.0 {
-                        let tip = (MITER_LIMIT - 1.0) * (max_stroke + shadow.spread);
-                        source.outset((tip, tip));
-                    }
-                    rect.join(filter.compute_fast_bounds(source));
+        for shadow in self.drop_shadows_visible() {
+            if let Some(filter) = shadow.get_drop_shadow_filter() {
+                let mut source = rect;
+                if mitered && shadow.spread > 0.0 {
+                    let tip = (MITER_LIMIT - 1.0) * (max_stroke + shadow.spread);
+                    source.outset((tip, tip));
                 }
+                rect.join(filter.compute_fast_bounds(source));
             }
         }
         Bounds::from_rect(&rect)
@@ -1514,10 +1512,6 @@ impl Shape {
             .filter(|shadow| shadow.style() == ShadowStyle::Inner && !shadow.hidden())
     }
 
-    pub fn shadows_visible(&self) -> impl DoubleEndedIterator<Item = &Shadow> {
-        self.shadows.iter().rev().filter(|shadow| !shadow.hidden())
-    }
-
     pub fn to_path_transform(&self) -> Option<Matrix> {
         match self.shape_type {
             Type::Path(_) | Type::Bool(_) => {
@@ -2571,6 +2565,35 @@ mod tests {
         assert!(extrect.bottom > 50.0 + 20.0);
     }
 
+    /// Inner shadows are drawn inside the shape; they must not inflate export
+    /// size (WebGL PNG surface uses `extrect`). Regression for #12386.
+    #[test]
+    fn leaf_extrect_ignores_inner_shadow_offset() {
+        let mut pool = ShapesPool::new();
+        pool.initialize(1);
+
+        let shape_id = Uuid::new_v4();
+        {
+            let shape = pool.add_shape(shape_id);
+            shape.set_shape_type(Type::Rect(Rect::default()));
+            shape.set_selrect(0.0, 0.0, 200.0, 200.0);
+            shape.add_shadow(inner_shadow(0.0, (0.0, 1.0)));
+        }
+
+        let shape = pool.get(&shape_id).expect("shape should exist");
+        let baseline = {
+            let mut no_shadow = shape.clone();
+            no_shadow.clear_shadows();
+            no_shadow.calculate_extrect(&pool, 1.0)
+        };
+        let extrect = shape.calculate_extrect(&pool, 1.0);
+
+        assert_eq!(extrect.height(), baseline.height());
+        assert_eq!(extrect.width(), baseline.width());
+        assert_eq!(extrect.height(), 200.0);
+        assert_eq!(extrect.width(), 200.0);
+    }
+
     #[test]
     fn test_apply_transform() {
         let mut shape = Shape::new(Uuid::new_v4());
diff --git a/render-wasm/src/shapes/shadows.rs b/render-wasm/src/shapes/shadows.rs
index 11a0e13295..b13c6d76bf 100644
--- a/render-wasm/src/shapes/shadows.rs
+++ b/render-wasm/src/shapes/shadows.rs
@@ -87,6 +87,10 @@ impl Shadow {
     }
 
     pub fn get_drop_shadow_filter(&self) -> Option<ImageFilter> {
+        if self.style == ShadowStyle::Inner {
+            return None;
+        }
+
         let sigma = radius_to_sigma(self.blur);
         let mut filter = image_filters::drop_shadow_only(
             (self.offset.0, self.offset.1),