diff --git a/src/js_misc.ml b/src/js_misc.ml
index 65f7b44..bfef103 100644
--- a/src/js_misc.ml
+++ b/src/js_misc.ml
@@ -28,17 +28,11 @@ type rows_or_columns =
 [@@deriving sexp, bin_io, variants, compare]
 
 let innerHeight () =
-  Js.Optdef.case
-    Dom_html.window##.innerHeight
-    (fun () -> Dom_html.document##.documentElement##.clientHeight)
-    Fn.id
+  Dom_html.window##.innerHeight
 ;;
 
 let innerWidth () =
-  Js.Optdef.case
-    Dom_html.window##.innerWidth
-    (fun () -> Dom_html.document##.documentElement##.clientWidth)
-    Fn.id
+  Dom_html.window##.innerWidth
 ;;
 
 let element_is_in_viewport (elt : Dom_html.element Js.t) =