diff --git a/webrender/src/border.rs b/webrender/src/border.rs
index a0e627a060..c602dca110 100644
--- a/webrender/src/border.rs
+++ b/webrender/src/border.rs
@@ -2,7 +2,7 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
-use api::{BorderSide, BorderStyle, BorderWidths, ClipAndScrollInfo, ColorF};
+use api::{BorderRadius, BorderSide, BorderStyle, BorderWidths, ClipAndScrollInfo, ColorF};
 use api::{LayerPoint, LayerRect};
 use api::{LayerPrimitiveInfo, LayerSize, NormalBorder, RepeatMode};
 use clip::ClipSource;
@@ -227,6 +227,48 @@ impl NormalBorderHelpers for NormalBorder {
     }
 }
 
+fn ensure_no_corner_overlap(radius: &mut BorderRadius, info: &LayerPrimitiveInfo) {
+    let mut ratio = 1.0;
+    let top_left_radius = &mut radius.top_left;
+    let top_right_radius = &mut radius.top_right;
+    let bottom_right_radius = &mut radius.bottom_right;
+    let bottom_left_radius = &mut radius.bottom_left;
+
+    let sum = top_left_radius.width + bottom_left_radius.width;
+    if info.rect.size.width < sum {
+        ratio = f32::min(ratio, info.rect.size.width / sum);
+    }
+
+    let sum = top_right_radius.width + bottom_right_radius.width;
+    if info.rect.size.width < sum {
+        ratio = f32::min(ratio, info.rect.size.width / sum);
+    }
+
+    let sum = top_left_radius.height + bottom_left_radius.height;
+    if info.rect.size.height < sum {
+        ratio = f32::min(ratio, info.rect.size.height / sum);
+    }
+
+    let sum = top_right_radius.height + bottom_right_radius.height;
+    if info.rect.size.height < sum {
+        ratio = f32::min(ratio, info.rect.size.height / sum);
+    }
+
+    if ratio < 1. {
+        top_left_radius.width *= ratio;
+        top_left_radius.height *= ratio;
+
+        top_right_radius.width *= ratio;
+        top_right_radius.height *= ratio;
+
+        bottom_left_radius.width *= ratio;
+        bottom_left_radius.height *= ratio;
+
+        bottom_right_radius.width *= ratio;
+        bottom_right_radius.height *= ratio;
+    }
+}
+
 impl FrameBuilder {
     fn add_normal_border_primitive(
         &mut self,
@@ -310,6 +352,9 @@ impl FrameBuilder {
         // out more often on CI (the actual cause is simply too many Servo processes and
         // threads being run on CI at once).
 
+        let mut border = *border;
+        ensure_no_corner_overlap(&mut border.radius, &info);
+
         let radius = &border.radius;
         let left = &border.left;
         let right = &border.right;
@@ -478,7 +523,7 @@ impl FrameBuilder {
 
             self.add_normal_border_primitive(
                 info,
-                border,
+                &border,
                 widths,
                 clip_and_scroll,
                 corner_instances,
@@ -880,4 +925,4 @@ impl ImageBorderSegment {
             tile_spacing,
         }
     }
-}
+}
\ No newline at end of file
diff --git a/wrench/reftests/border/border-clamp-corner-radius-ref.png b/wrench/reftests/border/border-clamp-corner-radius-ref.png
new file mode 100644
index 0000000000..e87d5873e2
Binary files /dev/null and b/wrench/reftests/border/border-clamp-corner-radius-ref.png differ
diff --git a/wrench/reftests/border/border-clamp-corner-radius.yaml b/wrench/reftests/border/border-clamp-corner-radius.yaml
new file mode 100644
index 0000000000..10859274c7
--- /dev/null
+++ b/wrench/reftests/border/border-clamp-corner-radius.yaml
@@ -0,0 +1,24 @@
+---
+root:
+  items:
+    - type: stacking-context
+      bounds: [0, 0, 420, 250]
+      items:
+        - type: border
+          bounds: [ 0, 0, 200, 200 ]
+          width: 10
+          border-type: normal
+          style: solid
+          radius: 180
+          color: blue
+        - type: border
+          bounds: [ 200, 0, 200, 200 ]
+          width: 10
+          border-type: normal
+          style: solid
+          radius:
+            top-left: [180, 180]
+            top-right: [0, 0]
+            bottom-left: [0, 0]
+            bottom-right: [180, 180]
+          color: blue
\ No newline at end of file
diff --git a/wrench/reftests/border/border-no-bogus-line-ref.png b/wrench/reftests/border/border-no-bogus-line-ref.png
index 52344a03fe..64c7a3afe5 100644
Binary files a/wrench/reftests/border/border-no-bogus-line-ref.png and b/wrench/reftests/border/border-no-bogus-line-ref.png differ
diff --git a/wrench/reftests/border/reftest.list b/wrench/reftests/border/reftest.list
index a8e95cc59d..883176536d 100644
--- a/wrench/reftests/border/reftest.list
+++ b/wrench/reftests/border/reftest.list
@@ -1,3 +1,4 @@
+== border-clamp-corner-radius.yaml border-clamp-corner-radius-ref.png
 == border-gradient-simple.yaml border-gradient-simple-ref.yaml
 == border-radial-gradient-simple.yaml border-radial-gradient-simple-ref.yaml
 == border-radii.yaml border-radii.png