diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 6547b1f424b..666762bc549 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -151,7 +151,7 @@ use crate::script_runtime::{
     CanGc, CommonScriptMsg, JSContext, Runtime, ScriptChan, ScriptPort, ScriptThreadEventCategory,
 };
 use crate::script_thread::{
-    ImageCacheMsg, MainThreadScriptChan, MainThreadScriptMsg, ScriptThread,
+    with_script_thread, ImageCacheMsg, MainThreadScriptChan, MainThreadScriptMsg, ScriptThread,
     SendableMainThreadScriptChan,
 };
 use crate::task_manager::TaskManager;
@@ -380,6 +380,8 @@ pub struct Window {
 
     /// Sizes of the various `<iframes>` that we might have on this [`Window`].
     /// This is used to:
+    ///  - Let same-`ScriptThread` `<iframe>`s know synchronously when their
+    ///    size has changed, ensuring that the next layout has the right size.
     ///  - Send the proper size for the `<iframe>` during new-Pipeline creation
     ///    when the `src` attribute changes.
     ///  - Let the `Constellation` know about `BrowsingContext` (one per `<iframe>`)
@@ -1982,6 +1984,24 @@ impl Window {
             return;
         }
 
+        // Batch resize message to any local `Pipeline`s now, rather than waiting for them
+        // to filter asynchronously through the `Constellation`. This allows the new value
+        // to be reflected immediately in layout.
+        let device_pixel_ratio = self.device_pixel_ratio();
+        with_script_thread(|script_thread| {
+            for iframe_size in new_iframe_sizes.values() {
+                script_thread.handle_resize_message(
+                    iframe_size.pipeline_id,
+                    WindowSizeData {
+                        initial_viewport: iframe_size.size,
+                        device_pixel_ratio,
+                    },
+                    // TODO: This might send an extra resize event. This can fixed by explicitly
+                    // supporting `<iframe>` creation when the size isn't known yet.
+                    WindowSizeType::Resize,
+                );
+            }
+        });
         // Send asynchronous updates to `Constellation.`
         let size_messages: Vec<_> = new_iframe_sizes
             .iter()
diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index dde26e9a970..2a72c475688 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -1546,8 +1546,10 @@ impl ScriptThread {
         // > the order it is found in the list.
         let documents_in_order = self.documents.borrow().documents_in_order();
 
-        // Note: the spec reads: "for doc in docs" at each step
-        // whereas this runs all steps per doc in docs.
+        // TODO: The specification reads: "for doc in docs" at each step whereas this runs all
+        // steps per doc in docs. Currently `<iframe>` resizing depends on a parent being able to
+        // queue resize events on a child and have those run in the same call to this method, so
+        // that needs to be sorted out to fix this.
         for pipeline_id in documents_in_order.iter() {
             let document = self
                 .documents
@@ -1619,8 +1621,6 @@ impl ScriptThread {
 
             // TODO: Mark paint timing from https://w3c.github.io/paint-timing.
 
-            // TODO(#31871): Update the rendering: consolidate all reflow calls into one here?
-
             #[cfg(feature = "webgpu")]
             document.update_rendering_of_webgpu_canvases();
 
@@ -2828,7 +2828,7 @@ impl ScriptThread {
 
     /// Batch window resize operations into a single "update the rendering" task,
     /// or, if a load is in progress, set the window size directly.
-    fn handle_resize_message(
+    pub(crate) fn handle_resize_message(
         &self,
         id: PipelineId,
         size: WindowSizeData,
@@ -2843,9 +2843,7 @@ impl ScriptThread {
             let mut loads = self.incomplete_loads.borrow_mut();
             if let Some(ref mut load) = loads.iter_mut().find(|load| load.pipeline_id == id) {
                 load.window_size = size;
-                return;
             }
-            warn!("resize sent to nonexistent pipeline");
         })
     }
 
diff --git a/tests/wpt/meta/css/css-values/dynamic-viewport-units-rule-cache.html.ini b/tests/wpt/meta/css/css-values/dynamic-viewport-units-rule-cache.html.ini
deleted file mode 100644
index 88f44ae9571..00000000000
--- a/tests/wpt/meta/css/css-values/dynamic-viewport-units-rule-cache.html.ini
+++ /dev/null
@@ -1,4 +0,0 @@
-[dynamic-viewport-units-rule-cache.html]
-  expected: TIMEOUT
-  [dynamic-viewport-units-rule-cache]
-    expected: TIMEOUT
diff --git a/tests/wpt/meta/css/cssom-view/MediaQueryList-addListener-handleEvent.html.ini b/tests/wpt/meta/css/cssom-view/MediaQueryList-addListener-handleEvent.html.ini
index c124d4bb540..037d7e0f951 100644
--- a/tests/wpt/meta/css/cssom-view/MediaQueryList-addListener-handleEvent.html.ini
+++ b/tests/wpt/meta/css/cssom-view/MediaQueryList-addListener-handleEvent.html.ini
@@ -4,12 +4,3 @@
 
   [throws if handleEvent is thruthy and not callable]
     expected: FAIL
-
-  [looks up handleEvent method on every event dispatch]
-    expected: FAIL
-
-  [doesn't look up handleEvent method on callable event listeners]
-    expected: FAIL
-
-  [rethrows errors when getting handleEvent]
-    expected: FAIL
diff --git a/tests/wpt/meta/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini b/tests/wpt/meta/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
index 7e55b5e346e..314dca9c1f5 100644
--- a/tests/wpt/meta/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
+++ b/tests/wpt/meta/css/cssom-view/MediaQueryList-addListener-removeListener.html.ini
@@ -1,18 +1,3 @@
 [MediaQueryList-addListener-removeListener.html]
   [listeners are called when <iframe> is resized]
     expected: FAIL
-
-  [listeners are called correct number of times]
-    expected: FAIL
-
-  [listeners are called in order they were added]
-    expected: FAIL
-
-  [listener that was added twice is called only once]
-    expected: FAIL
-
-  [listeners are called in order their MQLs were created]
-    expected: FAIL
-
-  [removing listener from one MQL doesn't remove it from all MQLs]
-    expected: FAIL
diff --git a/tests/wpt/meta/css/cssom-view/MediaQueryList-extends-EventTarget-interop.html.ini b/tests/wpt/meta/css/cssom-view/MediaQueryList-extends-EventTarget-interop.html.ini
deleted file mode 100644
index b5218650b98..00000000000
--- a/tests/wpt/meta/css/cssom-view/MediaQueryList-extends-EventTarget-interop.html.ini
+++ /dev/null
@@ -1,12 +0,0 @@
-[MediaQueryList-extends-EventTarget-interop.html]
-  [listener added with addListener and addEventListener (capture) is called twice]
-    expected: FAIL
-
-  [removeEventListener (capture) doesn't remove listener added with addListener]
-    expected: FAIL
-
-  [removeListener doesn't remove listener added with addEventListener (capture)]
-    expected: FAIL
-
-  [capturing event listener fires before non-capturing listener at target]
-    expected: FAIL
diff --git a/tests/wpt/meta/css/cssom-view/MediaQueryList-extends-EventTarget.html.ini b/tests/wpt/meta/css/cssom-view/MediaQueryList-extends-EventTarget.html.ini
deleted file mode 100644
index bfd64f1c58d..00000000000
--- a/tests/wpt/meta/css/cssom-view/MediaQueryList-extends-EventTarget.html.ini
+++ /dev/null
@@ -1,9 +0,0 @@
-[MediaQueryList-extends-EventTarget.html]
-  [onchange removes listener]
-    expected: FAIL
-
-  [listeners for "change" type are called]
-    expected: FAIL
-
-  [addEventListener "once" option is respected]
-    expected: FAIL
diff --git a/tests/wpt/meta/css/cssom-view/MediaQueryListEvent.html.ini b/tests/wpt/meta/css/cssom-view/MediaQueryListEvent.html.ini
deleted file mode 100644
index 2bff632780a..00000000000
--- a/tests/wpt/meta/css/cssom-view/MediaQueryListEvent.html.ini
+++ /dev/null
@@ -1,6 +0,0 @@
-[MediaQueryListEvent.html]
-  [argument of onchange]
-    expected: FAIL
-
-  [constructor of "change" event]
-    expected: FAIL
diff --git a/tests/wpt/meta/fetch/metadata/generated/element-img-environment-change.https.sub.html.ini b/tests/wpt/meta/fetch/metadata/generated/element-img-environment-change.https.sub.html.ini
index e1b5107c93c..cdb346e0520 100644
--- a/tests/wpt/meta/fetch/metadata/generated/element-img-environment-change.https.sub.html.ini
+++ b/tests/wpt/meta/fetch/metadata/generated/element-img-environment-change.https.sub.html.ini
@@ -1,5 +1,4 @@
 [element-img-environment-change.https.sub.html]
-  expected: TIMEOUT
   [sec-fetch-site - Cross-site, no attributes]
     expected: FAIL
 
@@ -59,3 +58,9 @@
 
   [sec-fetch-site - Same origin, no attributes]
     expected: FAIL
+
+  [sec-fetch-storage-access - Cross-site, no attributes]
+    expected: FAIL
+
+  [sec-fetch-storage-access - Same site, no attributes]
+    expected: FAIL
diff --git a/tests/wpt/meta/fetch/metadata/generated/element-img-environment-change.sub.html.ini b/tests/wpt/meta/fetch/metadata/generated/element-img-environment-change.sub.html.ini
index 5e6dca448af..9a39915caa5 100644
--- a/tests/wpt/meta/fetch/metadata/generated/element-img-environment-change.sub.html.ini
+++ b/tests/wpt/meta/fetch/metadata/generated/element-img-environment-change.sub.html.ini
@@ -1,46 +1,54 @@
 [element-img-environment-change.sub.html]
-  expected: TIMEOUT
   [sec-fetch-site - Not sent to non-trustworthy same-site destination, no attributes]
     expected: FAIL
 
   [sec-fetch-site - Not sent to non-trustworthy cross-site destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-mode - Not sent to non-trustworthy same-origin destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-mode - Not sent to non-trustworthy same-site destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-mode - Not sent to non-trustworthy cross-site destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-dest - Not sent to non-trustworthy same-origin destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-dest - Not sent to non-trustworthy same-site destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-dest - Not sent to non-trustworthy cross-site destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-user - Not sent to non-trustworthy same-origin destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-user - Not sent to non-trustworthy same-site destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-user - Not sent to non-trustworthy cross-site destination, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-site - HTTPS downgrade (header not sent), no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-site - HTTPS upgrade, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-site - HTTPS downgrade-upgrade, no attributes]
-    expected: NOTRUN
+    expected: FAIL
 
   [sec-fetch-site - Not sent to non-trustworthy same-origin destination, no attributes]
     expected: FAIL
+
+  [sec-fetch-storage-access - Not sent to non-trustworthy same-origin destination, no attributes]
+    expected: FAIL
+
+  [sec-fetch-storage-access - Not sent to non-trustworthy same-site destination, no attributes]
+    expected: FAIL
+
+  [sec-fetch-storage-access - Not sent to non-trustworthy cross-site destination, no attributes]
+    expected: FAIL
diff --git a/tests/wpt/meta/html/browsers/browsing-the-web/navigating-across-documents/initial-empty-document/iframe-src-aboutblank-navigate-immediately.html.ini b/tests/wpt/meta/html/browsers/browsing-the-web/navigating-across-documents/initial-empty-document/iframe-src-aboutblank-navigate-immediately.html.ini
index d7ccdbdf676..c5fc1407992 100644
--- a/tests/wpt/meta/html/browsers/browsing-the-web/navigating-across-documents/initial-empty-document/iframe-src-aboutblank-navigate-immediately.html.ini
+++ b/tests/wpt/meta/html/browsers/browsing-the-web/navigating-across-documents/initial-empty-document/iframe-src-aboutblank-navigate-immediately.html.ini
@@ -4,7 +4,7 @@
     expected: FAIL
 
   [Navigating to a different document with link click]
-    expected: TIMEOUT
+    expected: FAIL
 
   [Navigating to a different document with form submission]
-    expected: NOTRUN
+    expected: TIMEOUT