diff --git a/components/canvas/canvas_data.rs b/components/canvas/canvas_data.rs
index ea30589d0af..fd624b84463 100644
--- a/components/canvas/canvas_data.rs
+++ b/components/canvas/canvas_data.rs
@@ -447,7 +447,7 @@ impl<'a, B: Backend> CanvasData<'a, B> {
     pub(crate) fn draw_image(
         &mut self,
         image_data: &[u8],
-        image_size: Size2D<u64>,
+        image_size: Size2D<u32>,
         dest_rect: Rect<f64>,
         source_rect: Rect<f64>,
         smoothing_enabled: bool,
@@ -457,7 +457,7 @@ impl<'a, B: Backend> CanvasData<'a, B> {
         let source_rect = source_rect.ceil();
         // It discards the extra pixels (if any) that won't be painted
         let image_data = if Rect::from_size(image_size.to_f64()).contains_rect(&source_rect) {
-            pixels::rgba8_get_rect(image_data, image_size, source_rect.to_u64()).into()
+            pixels::rgba8_get_rect(image_data, image_size, source_rect.to_u32()).into()
         } else {
             image_data.into()
         };
@@ -1221,7 +1221,7 @@ impl<'a, B: Backend> CanvasData<'a, B> {
     }
 
     // https://html.spec.whatwg.org/multipage/#dom-context-2d-putimagedata
-    pub(crate) fn put_image_data(&mut self, mut imagedata: Vec<u8>, rect: Rect<u64>) {
+    pub(crate) fn put_image_data(&mut self, mut imagedata: Vec<u8>, rect: Rect<u32>) {
         assert_eq!(imagedata.len() % 4, 0);
         assert_eq!(rect.size.area() as usize, imagedata.len() / 4);
         pixels::rgba8_byte_swap_and_premultiply_inplace(&mut imagedata);
@@ -1310,8 +1310,8 @@ impl<'a, B: Backend> CanvasData<'a, B> {
     #[allow(unsafe_code)]
     pub(crate) fn read_pixels(
         &self,
-        read_rect: Option<Rect<u64>>,
-        canvas_size: Option<Size2D<u64>>,
+        read_rect: Option<Rect<u32>>,
+        canvas_size: Option<Size2D<u32>>,
     ) -> Snapshot {
         let canvas_size = canvas_size.unwrap_or(self.drawtarget.get_size().cast());
 
diff --git a/components/canvas/canvas_paint_thread.rs b/components/canvas/canvas_paint_thread.rs
index efadbf8d577..93aff081c35 100644
--- a/components/canvas/canvas_paint_thread.rs
+++ b/components/canvas/canvas_paint_thread.rs
@@ -187,7 +187,7 @@ impl<'a> CanvasPaintThread<'a> {
             Canvas2dMsg::DrawEmptyImage(image_size, dest_rect, source_rect) => {
                 self.canvas(canvas_id).draw_image(
                     &vec![0; image_size.area() as usize * 4],
-                    image_size.to_u64(),
+                    image_size,
                     dest_rect,
                     source_rect,
                     false,
@@ -203,10 +203,10 @@ impl<'a> CanvasPaintThread<'a> {
             ) => {
                 let image_data = self
                     .canvas(canvas_id)
-                    .read_pixels(Some(source_rect.to_u64()), Some(image_size.to_u64()));
+                    .read_pixels(Some(source_rect.to_u32()), Some(image_size));
                 self.canvas(other_canvas_id).draw_image(
                     image_data.data(),
-                    source_rect.size.to_u64(),
+                    source_rect.size.to_u32(),
                     dest_rect,
                     source_rect,
                     smoothing,
@@ -398,7 +398,7 @@ impl Canvas<'_> {
     fn draw_image(
         &mut self,
         data: &[u8],
-        size: Size2D<u64>,
+        size: Size2D<u32>,
         dest_rect: Rect<f64>,
         source_rect: Rect<f64>,
         smoothing_enabled: bool,
@@ -418,8 +418,8 @@ impl Canvas<'_> {
 
     fn read_pixels(
         &mut self,
-        read_rect: Option<Rect<u64>>,
-        canvas_size: Option<Size2D<u64>>,
+        read_rect: Option<Rect<u32>>,
+        canvas_size: Option<Size2D<u32>>,
     ) -> snapshot::Snapshot {
         match self {
             Canvas::Raqote(canvas_data) => canvas_data.read_pixels(read_rect, canvas_size),
@@ -612,7 +612,7 @@ impl Canvas<'_> {
         }
     }
 
-    fn put_image_data(&mut self, unwrap: Vec<u8>, rect: Rect<u64>) {
+    fn put_image_data(&mut self, unwrap: Vec<u8>, rect: Rect<u32>) {
         match self {
             Canvas::Raqote(canvas_data) => canvas_data.put_image_data(unwrap, rect),
         }
diff --git a/components/pixels/lib.rs b/components/pixels/lib.rs
index c1dbf35cbf3..3dda4d28bde 100644
--- a/components/pixels/lib.rs
+++ b/components/pixels/lib.rs
@@ -45,7 +45,7 @@ pub fn compute_rgba8_byte_length_if_within_limit(width: usize, height: usize) ->
         .filter(|v| *v <= MAX_IMAGE_BYTE_LENGTH)
 }
 
-pub fn rgba8_get_rect(pixels: &[u8], size: Size2D<u64>, rect: Rect<u64>) -> Cow<[u8]> {
+pub fn rgba8_get_rect(pixels: &[u8], size: Size2D<u32>, rect: Rect<u32>) -> Cow<[u8]> {
     assert!(!rect.is_empty());
     assert!(Rect::from_size(size).contains_rect(&rect));
     assert_eq!(pixels.len() % 4, 0);
@@ -106,18 +106,18 @@ pub fn multiply_u8_color(a: u8, b: u8) -> u8 {
 
 pub fn clip(
     mut origin: Point2D<i32>,
-    mut size: Size2D<u64>,
-    surface: Size2D<u64>,
-) -> Option<Rect<u64>> {
+    mut size: Size2D<u32>,
+    surface: Size2D<u32>,
+) -> Option<Rect<u32>> {
     if origin.x < 0 {
-        size.width = size.width.saturating_sub(-origin.x as u64);
+        size.width = size.width.saturating_sub(-origin.x as u32);
         origin.x = 0;
     }
     if origin.y < 0 {
-        size.height = size.height.saturating_sub(-origin.y as u64);
+        size.height = size.height.saturating_sub(-origin.y as u32);
         origin.y = 0;
     }
-    let origin = Point2D::new(origin.x as u64, origin.y as u64);
+    let origin = Point2D::new(origin.x as u32, origin.y as u32);
     Rect::new(origin, size)
         .intersection(&Rect::from_size(surface))
         .filter(|rect| !rect.is_empty())
diff --git a/components/script/canvas_context.rs b/components/script/canvas_context.rs
index ec388e039f1..aadbd656a0c 100644
--- a/components/script/canvas_context.rs
+++ b/components/script/canvas_context.rs
@@ -48,7 +48,7 @@ pub(crate) trait CanvasContext {
         true
     }
 
-    fn size(&self) -> Size2D<u64> {
+    fn size(&self) -> Size2D<u32> {
         self.canvas().size()
     }
 
@@ -73,12 +73,12 @@ pub(crate) trait CanvasContext {
 }
 
 pub(crate) trait CanvasHelpers {
-    fn size(&self) -> Size2D<u64>;
+    fn size(&self) -> Size2D<u32>;
     fn canvas(&self) -> Option<&HTMLCanvasElement>;
 }
 
 impl CanvasHelpers for HTMLCanvasElementOrOffscreenCanvas {
-    fn size(&self) -> Size2D<u64> {
+    fn size(&self) -> Size2D<u32> {
         match self {
             HTMLCanvasElementOrOffscreenCanvas::HTMLCanvasElement(canvas) => {
                 canvas.get_size().cast()
@@ -164,7 +164,7 @@ impl CanvasContext for RenderingContext {
         }
     }
 
-    fn size(&self) -> Size2D<u64> {
+    fn size(&self) -> Size2D<u32> {
         match self {
             RenderingContext::Placeholder(context) => (*context.context().unwrap()).size(),
             RenderingContext::Context2d(context) => context.size(),
@@ -251,7 +251,7 @@ impl CanvasContext for OffscreenRenderingContext {
         }
     }
 
-    fn size(&self) -> Size2D<u64> {
+    fn size(&self) -> Size2D<u32> {
         match self {
             OffscreenRenderingContext::Context2d(context) => context.size(),
         }
diff --git a/components/script/canvas_state.rs b/components/script/canvas_state.rs
index d788d2f5929..139579d2045 100644
--- a/components/script/canvas_state.rs
+++ b/components/script/canvas_state.rs
@@ -383,7 +383,7 @@ impl CanvasState {
         }
     }
 
-    pub(crate) fn get_rect(&self, canvas_size: Size2D<u64>, rect: Rect<u64>) -> Vec<u8> {
+    pub(crate) fn get_rect(&self, canvas_size: Size2D<u32>, rect: Rect<u32>) -> Vec<u8> {
         assert!(self.origin_is_clean());
         assert!(Rect::from_size(canvas_size).contains_rect(&rect));
 
@@ -531,11 +531,11 @@ impl CanvasState {
         };
 
         // Step 4. Establish the source and destination rectangles.
-        let video_size = snapshot.size().to_f64();
-        let dw = dw.unwrap_or(video_size.width);
-        let dh = dh.unwrap_or(video_size.height);
-        let sw = sw.unwrap_or(video_size.width);
-        let sh = sh.unwrap_or(video_size.height);
+        let video_size = snapshot.size();
+        let dw = dw.unwrap_or(video_size.width as f64);
+        let dh = dh.unwrap_or(video_size.height as f64);
+        let sw = sw.unwrap_or(video_size.width as f64);
+        let sh = sh.unwrap_or(video_size.height as f64);
 
         let (source_rect, dest_rect) =
             self.adjust_source_dest_rects(video_size, sx, sy, sw, sh, dx, dy, dw, dh);
@@ -577,7 +577,7 @@ impl CanvasState {
         let sw = sw.unwrap_or(canvas_size.width as f64);
         let sh = sh.unwrap_or(canvas_size.height as f64);
 
-        let image_size = Size2D::new(canvas_size.width as f64, canvas_size.height as f64);
+        let image_size = Size2D::new(canvas_size.width, canvas_size.height);
         // 2. Establish the source and destination rectangles
         let (source_rect, dest_rect) =
             self.adjust_source_dest_rects(image_size, sx, sy, sw, sh, dx, dy, dw, dh);
@@ -632,7 +632,7 @@ impl CanvasState {
         let sw = sw.unwrap_or(canvas_size.width as f64);
         let sh = sh.unwrap_or(canvas_size.height as f64);
 
-        let image_size = Size2D::new(canvas_size.width as f64, canvas_size.height as f64);
+        let image_size = Size2D::new(canvas_size.width, canvas_size.height);
         // 2. Establish the source and destination rectangles
         let (source_rect, dest_rect) =
             self.adjust_source_dest_rects(image_size, sx, sy, sw, sh, dx, dy, dw, dh);
@@ -702,12 +702,12 @@ impl CanvasState {
         let snapshot = self
             .fetch_image_data(url, cors_setting)
             .ok_or(Error::InvalidState)?;
-        let image_size = snapshot.size().to_f64();
+        let image_size = snapshot.size();
 
-        let dw = dw.unwrap_or(image_size.width);
-        let dh = dh.unwrap_or(image_size.height);
-        let sw = sw.unwrap_or(image_size.width);
-        let sh = sh.unwrap_or(image_size.height);
+        let dw = dw.unwrap_or(image_size.width as f64);
+        let dh = dh.unwrap_or(image_size.height as f64);
+        let sw = sw.unwrap_or(image_size.width as f64);
+        let sh = sh.unwrap_or(image_size.height as f64);
 
         // Establish the source and destination rectangles
         let (source_rect, dest_rect) =
@@ -741,7 +741,7 @@ impl CanvasState {
     #[allow(clippy::too_many_arguments)]
     fn adjust_source_dest_rects(
         &self,
-        image_size: Size2D<f64>,
+        image_size: Size2D<u32>,
         sx: f64,
         sy: f64,
         sw: f64,
@@ -766,7 +766,7 @@ impl CanvasState {
         // When the source rectangle is outside the source image,
         // the source rectangle must be clipped to the source image
         let source_rect_clipped = source_rect
-            .intersection(&image_rect)
+            .intersection(&image_rect.to_f64())
             .unwrap_or(Rect::zero());
 
         // Width and height ratios between the non clipped and clipped source rectangles
@@ -1486,7 +1486,7 @@ impl CanvasState {
     #[allow(clippy::too_many_arguments)]
     pub(crate) fn get_image_data(
         &self,
-        canvas_size: Size2D<u64>,
+        canvas_size: Size2D<u32>,
         global: &GlobalScope,
         sx: i32,
         sy: i32,
@@ -1506,7 +1506,7 @@ impl CanvasState {
         }
 
         let (origin, size) = adjust_size_sign(Point2D::new(sx, sy), Size2D::new(sw, sh));
-        let read_rect = match pixels::clip(origin, size.to_u64(), canvas_size) {
+        let read_rect = match pixels::clip(origin, size.to_u32(), canvas_size) {
             Some(rect) => rect,
             None => {
                 // All the pixels are outside the canvas surface.
@@ -1526,7 +1526,7 @@ impl CanvasState {
     // https://html.spec.whatwg.org/multipage/#dom-context-2d-putimagedata
     pub(crate) fn put_image_data(
         &self,
-        canvas_size: Size2D<u64>,
+        canvas_size: Size2D<u32>,
         imagedata: &ImageData,
         dx: i32,
         dy: i32,
@@ -1547,7 +1547,7 @@ impl CanvasState {
     #[allow(unsafe_code, clippy::too_many_arguments)]
     pub(crate) fn put_image_data_(
         &self,
-        canvas_size: Size2D<u64>,
+        canvas_size: Size2D<u32>,
         imagedata: &ImageData,
         dx: i32,
         dy: i32,
@@ -1579,7 +1579,7 @@ impl CanvasState {
             Point2D::new(dirty_x, dirty_y),
             Size2D::new(dirty_width, dirty_height),
         );
-        let src_rect = match pixels::clip(src_origin, src_size.to_u64(), imagedata_size.to_u64()) {
+        let src_rect = match pixels::clip(src_origin, src_size.to_u32(), imagedata_size.to_u32()) {
             Some(rect) => rect,
             None => return,
         };
diff --git a/components/script/dom/htmlcanvaselement.rs b/components/script/dom/htmlcanvaselement.rs
index 025328dd78c..9c688678039 100644
--- a/components/script/dom/htmlcanvaselement.rs
+++ b/components/script/dom/htmlcanvaselement.rs
@@ -397,8 +397,8 @@ impl HTMLCanvasElement {
         // u32 can't panic, since the data comes from a canvas which is always smaller than
         // u32::MAX.
         let canvas_data = snapshot.data();
-        let width = snapshot.size().width as u32;
-        let height = snapshot.size().height as u32;
+        let width = snapshot.size().width;
+        let height = snapshot.size().height;
 
         match image_type {
             EncodedImageType::Png => {
diff --git a/components/script/dom/imagedata.rs b/components/script/dom/imagedata.rs
index fdb5fbb8942..a834abdae78 100644
--- a/components/script/dom/imagedata.rs
+++ b/components/script/dom/imagedata.rs
@@ -154,8 +154,8 @@ impl ImageData {
     }
 
     #[allow(unsafe_code)]
-    pub(crate) unsafe fn get_rect(&self, rect: Rect<u64>) -> Cow<[u8]> {
-        pixels::rgba8_get_rect(self.as_slice(), self.get_size().to_u64(), rect)
+    pub(crate) unsafe fn get_rect(&self, rect: Rect<u32>) -> Cow<[u8]> {
+        pixels::rgba8_get_rect(self.as_slice(), self.get_size().to_u32(), rect)
     }
 
     pub(crate) fn get_size(&self) -> Size2D<u32> {
diff --git a/components/script/dom/offscreencanvas.rs b/components/script/dom/offscreencanvas.rs
index e848ad862f8..cbcffb40e3e 100644
--- a/components/script/dom/offscreencanvas.rs
+++ b/components/script/dom/offscreencanvas.rs
@@ -72,8 +72,11 @@ impl OffscreenCanvas {
         )
     }
 
-    pub(crate) fn get_size(&self) -> Size2D<u64> {
-        Size2D::new(self.Width(), self.Height())
+    pub(crate) fn get_size(&self) -> Size2D<u32> {
+        Size2D::new(
+            self.Width().try_into().unwrap_or(u32::MAX),
+            self.Height().try_into().unwrap_or(u32::MAX),
+        )
     }
 
     pub(crate) fn origin_is_clean(&self) -> bool {
diff --git a/components/script/dom/webgl2renderingcontext.rs b/components/script/dom/webgl2renderingcontext.rs
index d2bbf3bba57..8f2bf9c2fcc 100644
--- a/components/script/dom/webgl2renderingcontext.rs
+++ b/components/script/dom/webgl2renderingcontext.rs
@@ -534,7 +534,7 @@ impl WebGL2RenderingContext {
             let src_origin = Point2D::new(x, y);
             let src_size = Size2D::new(width as u32, height as u32);
             let fb_size = Size2D::new(fb_width as u32, fb_height as u32);
-            match pixels::clip(src_origin, src_size.to_u64(), fb_size.to_u64()) {
+            match pixels::clip(src_origin, src_size.to_u32(), fb_size.to_u32()) {
                 Some(rect) => rect.to_u32(),
                 None => return,
             }
@@ -2183,7 +2183,7 @@ impl WebGL2RenderingContextMethods<crate::DomTypeHolder> for WebGL2RenderingCont
             let src_origin = Point2D::new(x, y);
             let src_size = Size2D::new(width as u32, height as u32);
             let fb_size = Size2D::new(fb_width as u32, fb_height as u32);
-            if pixels::clip(src_origin, src_size.to_u64(), fb_size.to_u64()).is_none() {
+            if pixels::clip(src_origin, src_size.to_u32(), fb_size.to_u32()).is_none() {
                 return;
             }
         }
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 70463ae1528..9b8ee461979 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -3838,7 +3838,7 @@ impl WebGLRenderingContextMethods<crate::DomTypeHolder> for WebGLRenderingContex
         let src_origin = Point2D::new(x, y);
         let src_size = Size2D::new(width as u32, height as u32);
         let fb_size = Size2D::new(fb_width as u32, fb_height as u32);
-        let src_rect = match pixels::clip(src_origin, src_size.to_u64(), fb_size.to_u64()) {
+        let src_rect = match pixels::clip(src_origin, src_size.to_u32(), fb_size.to_u32()) {
             Some(rect) => rect,
             None => return,
         };
diff --git a/components/script/dom/webgpu/gpucanvascontext.rs b/components/script/dom/webgpu/gpucanvascontext.rs
index 359b1b14003..9bf43c77bf5 100644
--- a/components/script/dom/webgpu/gpucanvascontext.rs
+++ b/components/script/dom/webgpu/gpucanvascontext.rs
@@ -167,8 +167,8 @@ impl GPUCanvasContext {
             // causes FAIL on webgpu:web_platform,canvas,configure:usage:*
             usage: configuration.usage | GPUTextureUsageConstants::COPY_SRC,
             size: GPUExtent3D::GPUExtent3DDict(GPUExtent3DDict {
-                width: size.width as u32,
-                height: size.height as u32,
+                width: size.width,
+                height: size.height,
                 depthOrArrayLayers: 1,
             }),
             viewFormats: configuration.viewFormats.clone(),
diff --git a/components/script/dom/webxr/xrwebgllayer.rs b/components/script/dom/webxr/xrwebgllayer.rs
index 0e93e583c6f..0d32b10cf47 100644
--- a/components/script/dom/webxr/xrwebgllayer.rs
+++ b/components/script/dom/webxr/xrwebgllayer.rs
@@ -129,10 +129,7 @@ impl XRWebGLLayer {
                 HTMLCanvasElementOrOffscreenCanvas::HTMLCanvasElement(canvas) => canvas.get_size(),
                 HTMLCanvasElementOrOffscreenCanvas::OffscreenCanvas(canvas) => {
                     let size = canvas.get_size();
-                    Size2D::new(
-                        size.width.try_into().unwrap_or(0),
-                        size.height.try_into().unwrap_or(0),
-                    )
+                    Size2D::new(size.width, size.height)
                 },
             };
             Size2D::from_untyped(size)
diff --git a/components/shared/canvas/canvas.rs b/components/shared/canvas/canvas.rs
index 850f5f9bd9a..283be0d458e 100644
--- a/components/shared/canvas/canvas.rs
+++ b/components/shared/canvas/canvas.rs
@@ -89,8 +89,8 @@ pub enum Canvas2dMsg {
     Arc(Point2D<f32>, f32, f32, f32, bool),
     ArcTo(Point2D<f32>, Point2D<f32>, f32),
     DrawImage(IpcSnapshot, Rect<f64>, Rect<f64>, bool),
-    DrawEmptyImage(Size2D<f64>, Rect<f64>, Rect<f64>),
-    DrawImageInOther(CanvasId, Size2D<f64>, Rect<f64>, Rect<f64>, bool),
+    DrawEmptyImage(Size2D<u32>, Rect<f64>, Rect<f64>),
+    DrawImageInOther(CanvasId, Size2D<u32>, Rect<f64>, Rect<f64>, bool),
     BeginPath,
     BezierCurveTo(Point2D<f32>, Point2D<f32>, Point2D<f32>),
     ClearRect(Rect<f32>),
@@ -102,14 +102,14 @@ pub enum Canvas2dMsg {
     FillPath(FillOrStrokeStyle, Vec<PathSegment>),
     FillText(String, f64, f64, Option<f64>, FillOrStrokeStyle, bool),
     FillRect(Rect<f32>, FillOrStrokeStyle),
-    GetImageData(Rect<u64>, Size2D<u64>, IpcSender<IpcSnapshot>),
+    GetImageData(Rect<u32>, Size2D<u32>, IpcSender<IpcSnapshot>),
     GetTransform(IpcSender<Transform2D<f32>>),
     IsPointInCurrentPath(f64, f64, FillRule, IpcSender<bool>),
     IsPointInPath(Vec<PathSegment>, f64, f64, FillRule, IpcSender<bool>),
     LineTo(Point2D<f32>),
     MoveTo(Point2D<f32>),
     MeasureText(String, IpcSender<TextMetrics>),
-    PutImageData(Rect<u64>, IpcBytesReceiver),
+    PutImageData(Rect<u32>, IpcBytesReceiver),
     QuadraticCurveTo(Point2D<f32>, Point2D<f32>),
     Rect(Rect<f32>),
     RestoreContext,
diff --git a/components/shared/snapshot/lib.rs b/components/shared/snapshot/lib.rs
index 7f0111f7a79..590de3666ad 100644
--- a/components/shared/snapshot/lib.rs
+++ b/components/shared/snapshot/lib.rs
@@ -87,7 +87,7 @@ pub type IpcSnapshot = Snapshot<IpcSharedMemory>;
 /// <https://gpuweb.github.io/gpuweb/#abstract-opdef-get-a-copy-of-the-image-contents-of-a-context>
 #[derive(Clone, Debug, Deserialize, MallocSizeOf, Serialize)]
 pub struct Snapshot<T = Data> {
-    size: Size2D<u64>,
+    size: Size2D<u32>,
     /// internal data (can be any format it will be converted on use if needed)
     data: T,
     /// RGBA/BGRA (reflect internal data)
@@ -97,7 +97,7 @@ pub struct Snapshot<T = Data> {
 }
 
 impl<T> Snapshot<T> {
-    pub const fn size(&self) -> Size2D<u64> {
+    pub const fn size(&self) -> Size2D<u32> {
         self.size
     }
 
@@ -131,7 +131,7 @@ impl Snapshot<Data> {
     }
 
     /// Returns snapshot with provided size that is black transparent alpha
-    pub fn cleared(size: Size2D<u64>) -> Self {
+    pub fn cleared(size: Size2D<u32>) -> Self {
         Self {
             size,
             data: Data::Owned(vec![0; size.area() as usize * 4]),
@@ -143,7 +143,7 @@ impl Snapshot<Data> {
     }
 
     pub fn from_vec(
-        size: Size2D<u64>,
+        size: Size2D<u32>,
         format: PixelFormat,
         alpha_mode: AlphaMode,
         data: Vec<u8>,
@@ -157,7 +157,7 @@ impl Snapshot<Data> {
     }
 
     pub fn from_shared_memory(
-        size: Size2D<u64>,
+        size: Size2D<u32>,
         format: PixelFormat,
         alpha_mode: AlphaMode,
         ism: IpcSharedMemory,
@@ -177,7 +177,7 @@ impl Snapshot<Data> {
     /// This is safe if data is owned by this process only
     /// (ownership is transferred on send)
     pub unsafe fn from_shared_memory(
-        size: Size2D<u64>,
+        size: Size2D<u32>,
         format: PixelFormat,
         alpha_mode: AlphaMode,
         ism: IpcSharedMemory,