diff --git a/docs/example_wasm_bg.wasm b/docs/example_wasm_bg.wasm
index dee00d47..5c15348f 100644
Binary files a/docs/example_wasm_bg.wasm and b/docs/example_wasm_bg.wasm differ
diff --git a/emigui/src/collapsing_header.rs b/emigui/src/collapsing_header.rs
index a65f8d6a..3fe901fd 100644
--- a/emigui/src/collapsing_header.rs
+++ b/emigui/src/collapsing_header.rs
@@ -118,7 +118,11 @@ impl CollapsingHeader {
 
                 add_contents(region);
 
-                region.bounding_size.y = region.bounding_size.y.min(max_height);
+                region.child_bounds.max.y = region
+                    .child_bounds
+                    .max
+                    .y
+                    .min(region.child_bounds.min.y + max_height);
             });
         } else if state.open {
             region.indent(id, add_contents);
diff --git a/emigui/src/floating.rs b/emigui/src/floating.rs
index 08a374c2..2d3fc889 100644
--- a/emigui/src/floating.rs
+++ b/emigui/src/floating.rs
@@ -66,7 +66,7 @@ impl Floating {
             Rect::from_min_size(state.outer_pos, Vec2::infinity()),
         );
         add_contents(&mut region);
-        let size = region.bounding_size.ceil();
+        let size = region.bounding_size().ceil();
 
         state.outer_rect = Rect::from_min_size(state.outer_pos, size);
         let move_interact = ctx.interact(layer, &state.outer_rect, Some(id.with("move")));
diff --git a/emigui/src/frame.rs b/emigui/src/frame.rs
index 9ce4068c..a1fa4f83 100644
--- a/emigui/src/frame.rs
+++ b/emigui/src/frame.rs
@@ -19,7 +19,7 @@ impl Frame {
         add_contents(&mut child_region);
 
         // TODO: handle the last item_spacing in a nicer way
-        let inner_size = child_region.bounding_size;
+        let inner_size = child_region.bounding_size();
         let inner_size = inner_size.ceil(); // TODO: round to pixel
 
         let outer_rect = Rect::from_min_size(outer_pos, margin + inner_size + margin);
@@ -36,6 +36,9 @@ impl Frame {
             },
         );
 
-        region.bounding_size = margin + child_region.bounding_size + margin; // TODO: this is not really right
+        // TODO: move up corsor?
+        region
+            .child_bounds
+            .extend_with(child_region.child_bounds.max + margin);
     }
 }
diff --git a/emigui/src/layout.rs b/emigui/src/layout.rs
index 1d7e5237..fe59bd65 100644
--- a/emigui/src/layout.rs
+++ b/emigui/src/layout.rs
@@ -110,7 +110,7 @@ pub fn show_popup(ctx: &Arc<Context>, window_pos: Pos2, add_contents: impl FnOnc
     // Now insert popup background:
 
     // TODO: handle the last item_spacing in a nicer way
-    let inner_size = contents_region.bounding_size - style.item_spacing;
+    let inner_size = contents_region.bounding_size() - style.item_spacing;
     let outer_size = inner_size + 2.0 * window_padding;
 
     let rect = Rect::from_min_size(window_pos, outer_size);
diff --git a/emigui/src/math.rs b/emigui/src/math.rs
index 46f21e26..9e83ebb0 100644
--- a/emigui/src/math.rs
+++ b/emigui/src/math.rs
@@ -392,6 +392,7 @@ impl Rect {
         *self = self.translate(center - self.center());
     }
 
+    #[must_use]
     pub fn contains(&self, p: Pos2) -> bool {
         self.min.x <= p.x
             && p.x <= self.min.x + self.size().x
@@ -399,6 +400,11 @@ impl Rect {
             && p.y <= self.min.y + self.size().y
     }
 
+    pub fn extend_with(&mut self, p: Pos2) {
+        self.min = self.min.min(p);
+        self.max = self.max.max(p);
+    }
+
     pub fn center(&self) -> Pos2 {
         Pos2 {
             x: self.min.x + self.size().x / 2.0,
diff --git a/emigui/src/region.rs b/emigui/src/region.rs
index 38a9a870..48897f23 100644
--- a/emigui/src/region.rs
+++ b/emigui/src/region.rs
@@ -30,13 +30,11 @@ pub struct Region {
     /// Note that the size may be infinite in one or both dimensions.
     /// The widgets will TRY to fit within the rect,
     /// but may overflow (which you will see in bounding_size).
-    pub(crate) desired_rect: Rect, // TODO: rename desired_rect
+    pub(crate) desired_rect: Rect, // TODO: rename
 
     /// Bounding box of children.
-    /// We keep track of our max-size along the orthogonal to self.dir
-    /// Initially set to zero.
-    /// TODO: make into `child_bounds: Rect`
-    pub(crate) bounding_size: Vec2,
+    /// Initially set to Rect::nothing().
+    pub(crate) child_bounds: Rect,
 
     /// Overide default style in this region
     pub(crate) style: Style,
@@ -65,7 +63,7 @@ impl Region {
             layer,
             clip_rect: rect.expand(CLIP_RECT_MARGIN),
             desired_rect: rect,
-            bounding_size: Vec2::default(),
+            child_bounds: Rect::from_min_size(rect.min, Vec2::zero()), // TODO: Rect::nothing() ?
             style,
             cursor: rect.min,
             dir: Direction::Vertical,
@@ -85,7 +83,7 @@ impl Region {
             clip_rect,
             desired_rect: child_rect,
             cursor: child_rect.min,
-            bounding_size: vec2(0.0, 0.0),
+            child_bounds: Rect::from_min_size(child_rect.min, Vec2::zero()), // TODO: Rect::nothing() ?
             dir: self.dir,
             align: self.align,
         }
@@ -170,6 +168,11 @@ impl Region {
         self.desired_rect.max - self.cursor
     }
 
+    /// Size of content
+    pub fn bounding_size(&self) -> Vec2 {
+        self.child_bounds.max - self.desired_rect.min
+    }
+
     pub fn direction(&self) -> Direction {
         self.dir
     }
@@ -199,7 +202,7 @@ impl Region {
             ..self.child_region(child_rect)
         };
         add_contents(&mut child_region);
-        self.reserve_space_without_padding(child_region.bounding_size);
+        self.reserve_space_without_padding(child_region.bounding_size());
     }
 
     /// Create a child region which is indented to the right
@@ -216,7 +219,7 @@ impl Region {
             ..self.child_region(child_rect)
         };
         add_contents(&mut child_region);
-        let size = child_region.bounding_size;
+        let size = child_region.bounding_size();
 
         // draw a grey line on the left to mark the region
         let line_start = child_rect.min - indent * 0.5;
@@ -269,7 +272,7 @@ impl Region {
             ..self.child_region(child_rect)
         };
         add_contents(&mut child_region);
-        let size = child_region.bounding_size;
+        let size = child_region.bounding_size();
         self.reserve_space_without_padding(size);
     }
 
@@ -316,7 +319,7 @@ impl Region {
 
         let mut max_height = 0.0;
         for region in columns {
-            let size = region.bounding_size;
+            let size = region.bounding_size();
             max_height = size.y.max(max_height);
         }
 
@@ -382,18 +385,16 @@ impl Region {
                 Align::Center => 0.5 * (self.available_height() - size.y),
                 Align::Max => self.available_height() - size.y,
             };
+            self.child_bounds.extend_with(self.cursor + size);
             self.cursor.x += size.x;
-            self.bounding_size.x += size.x;
-            self.bounding_size.y = self.bounding_size.y.max(size.y);
         } else {
             pos.x += match self.align {
                 Align::Min => 0.0,
                 Align::Center => 0.5 * (self.available_width() - size.x),
                 Align::Max => self.available_width() - size.x,
             };
+            self.child_bounds.extend_with(self.cursor + size);
             self.cursor.y += size.y;
-            self.bounding_size.y += size.y;
-            self.bounding_size.x = self.bounding_size.x.max(size.x);
         }
         pos
     }
diff --git a/emigui/src/resize.rs b/emigui/src/resize.rs
index b521d494..00148557 100644
--- a/emigui/src/resize.rs
+++ b/emigui/src/resize.rs
@@ -103,8 +103,7 @@ impl Resize {
         let desired_size = {
             let mut contents_region = region.child_region(inner_rect);
             add_contents(&mut contents_region);
-            let desired_size = contents_region.bounding_size;
-            desired_size
+            contents_region.bounding_size()
         };
         let desired_size = desired_size.ceil(); // Avoid rounding errors in math
 
diff --git a/emigui/src/scroll_area.rs b/emigui/src/scroll_area.rs
index 77730905..f9add704 100644
--- a/emigui/src/scroll_area.rs
+++ b/emigui/src/scroll_area.rs
@@ -53,7 +53,7 @@ impl ScrollArea {
         content_region.cursor -= state.offset;
         content_region.desired_rect = content_region.desired_rect.translate(-state.offset);
         add_contents(&mut content_region);
-        let content_size = content_region.bounding_size;
+        let content_size = content_region.bounding_size();
 
         let content_interact = ctx.interact(
             outer_region.layer,
diff --git a/emigui/src/window.rs b/emigui/src/window.rs
index f04b0a0a..c62f2474 100644
--- a/emigui/src/window.rs
+++ b/emigui/src/window.rs
@@ -157,7 +157,7 @@ impl Window {
         add_contents(&mut contents_region);
 
         // TODO: handle the last item_spacing in a nicer way
-        let desired_inner_size = contents_region.bounding_size - style.item_spacing;
+        let desired_inner_size = contents_region.bounding_size() - style.item_spacing;
         let desired_inner_size = desired_inner_size.ceil(); // Avoid rounding errors in math
 
         let mut new_inner_size = state.inner_size;