diff --git a/components/script/dom/htmliframeelement.rs b/components/script/dom/htmliframeelement.rs
index 6f1ee07658f..93a14f16fee 100644
--- a/components/script/dom/htmliframeelement.rs
+++ b/components/script/dom/htmliframeelement.rs
@@ -26,6 +26,7 @@ use crate::dom::windowproxy::WindowProxy;
 use crate::script_thread::ScriptThread;
 use crate::task_source::TaskSource;
 use dom_struct::dom_struct;
+use euclid::TypedSize2D;
 use html5ever::{LocalName, Prefix};
 use ipc_channel::ipc;
 use msg::constellation_msg::{BrowsingContextId, PipelineId, TopLevelBrowsingContextId};
@@ -34,6 +35,7 @@ use script_layout_interface::message::ReflowGoal;
 use script_traits::IFrameSandboxState::{IFrameSandboxed, IFrameUnsandboxed};
 use script_traits::{
     IFrameLoadInfo, IFrameLoadInfoWithData, JsEvalResult, LoadData, UpdatePipelineIdReason,
+    WindowSizeData,
 };
 use script_traits::{NewLayoutInfo, ScriptMsg};
 use servo_config::prefs::PREFS;
@@ -192,7 +194,16 @@ impl HTMLIFrameElement {
                     load_data: load_data.unwrap(),
                     pipeline_port: pipeline_receiver,
                     content_process_shutdown_chan: None,
-                    window_size: None,
+                    window_size: Some(WindowSizeData {
+                        initial_viewport: {
+                            let rect = self.upcast::<Node>().bounding_content_box_or_zero();
+                            TypedSize2D::new(
+                                rect.size.width.to_f32_px(),
+                                rect.size.height.to_f32_px(),
+                            )
+                        },
+                        device_pixel_ratio: window.device_pixel_ratio(),
+                    }),
                     layout_threads: PREFS.get("layout.threads").as_u64().expect("count") as usize,
                 };
 
diff --git a/tests/wpt/metadata/css/cssom-view/matchMedia.xht.ini b/tests/wpt/metadata/css/cssom-view/matchMedia.xht.ini
index e30cdec585a..b245ee1cb1f 100644
--- a/tests/wpt/metadata/css/cssom-view/matchMedia.xht.ini
+++ b/tests/wpt/metadata/css/cssom-view/matchMedia.xht.ini
@@ -4,18 +4,9 @@
   [window.matchMedia exists]
     expected: FAIL
 
-  [MediaQueryList.matches for "(max-width: 199px), all and (min-width: 200px)"]
-    expected: FAIL
-
   [MediaQueryList.matches for "(min-aspect-ratio: 1/1)"]
     expected: FAIL
 
-  [MediaQueryList.matches for "(width: 200px)"]
-    expected: FAIL
-
-  [MediaQueryList.matches for "(min-width: 150px)"]
-    expected: FAIL
-
   [Resize iframe from 200x100 to 200x50, then to 100x50]
     expected: NOTRUN
 
diff --git a/tests/wpt/metadata/css/cssom/getComputedStyle-detached-subtree.html.ini b/tests/wpt/metadata/css/cssom/getComputedStyle-detached-subtree.html.ini
index 764bd3e7169..efdf26ad1d1 100644
--- a/tests/wpt/metadata/css/cssom/getComputedStyle-detached-subtree.html.ini
+++ b/tests/wpt/metadata/css/cssom/getComputedStyle-detached-subtree.html.ini
@@ -1,2 +1,8 @@
 [getComputedStyle-detached-subtree.html]
   expected: ERROR
+  [getComputedStyle returns no style for element in non-rendered iframe (display: none) from iframe's window]
+    expected: FAIL
+
+  [getComputedStyle returns no style for element in non-rendered iframe (display: none)]
+    expected: FAIL
+