diff --git a/components/net/image_cache_task.rs b/components/net/image_cache_task.rs
index 9739e89ddfc..4ec3516d3b4 100644
--- a/components/net/image_cache_task.rs
+++ b/components/net/image_cache_task.rs
@@ -460,7 +460,7 @@ pub fn new_image_cache_task(resource_task: ResourceTask) -> ImageCacheTask {
 
         // Preload the placeholder image, used when images fail to load.
         let mut placeholder_path = resources_dir_path();
-        placeholder_path.push("rippy.jpg");
+        placeholder_path.push("rippy.png");
 
         let mut image_data = vec![];
         let result = File::open(&placeholder_path).and_then(|mut file| {
diff --git a/resources/rippy.jpg b/resources/rippy.png
similarity index 100%
rename from resources/rippy.jpg
rename to resources/rippy.png
diff --git a/tests/wpt/mozilla/tests/css/no-image-ref.html b/tests/wpt/mozilla/tests/css/no-image-ref.html
index 40ce07f789e..0d53ae51ac6 100644
--- a/tests/wpt/mozilla/tests/css/no-image-ref.html
+++ b/tests/wpt/mozilla/tests/css/no-image-ref.html
@@ -1 +1 @@
-<img width="100px" height="100px" src="rippy.jpg">
+<img width="100px" height="100px" src="rippy.png">