diff --git a/src/lib.rs b/src/lib.rs
index 6d72cce..cb22688 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -27,8 +27,6 @@ use std::{ffi::c_void, fmt, time::Duration};
 
 #[cfg(target_arch = "wasm32")]
 use std::panic;
-#[cfg(target_arch = "wasm32")]
-use web_sys::HtmlElement;
 
 #[cfg(target_os = "macos")]
 use os::macos as imp;
diff --git a/src/os/wasm/mod.rs b/src/os/wasm/mod.rs
index be75649..d11c729 100644
--- a/src/os/wasm/mod.rs
+++ b/src/os/wasm/mod.rs
@@ -184,7 +184,7 @@ impl Window {
             closure.forget();
         }
 
-        let mut window = Window {
+        Ok(Window {
             width: width as u32,
             height: height as u32,
             bg_color: 0,
@@ -196,9 +196,7 @@ impl Window {
             menu_counter: MenuHandle(0),
             menus: Vec::new(),
             raw_handle_id,
-        };
-
-        Ok(window)
+        })
     }
 
     fn create_2d_context(&self) -> CanvasRenderingContext2d {
@@ -426,8 +424,10 @@ impl Window {
 
     #[inline]
     pub fn is_active(&mut self) -> bool {
-        let document = window().unwrap().document().unwrap();
-        document.active_element().unwrap_or(return false) == **self.canvas
+        window()
+            .and_then(|window| window.document())
+            .and_then(|document| document.active_element())
+            .map_or(false, |element| element == **self.canvas)
     }
 
     #[inline]
diff --git a/src/rate.rs b/src/rate.rs
index ab340dd..39ef936 100644
--- a/src/rate.rs
+++ b/src/rate.rs
@@ -5,11 +5,13 @@ use instant::{Duration, Instant};
 #[cfg(not(target_arch = "wasm32"))]
 use std::time::{Duration, Instant};
 
+#[cfg_attr(target_arch = "wasm32", allow(unused))]
 pub struct UpdateRate {
     target_rate: Option<Duration>,
     prev_time: Instant,
 }
 
+#[cfg_attr(target_arch = "wasm32", allow(unused))]
 impl UpdateRate {
     pub fn new() -> UpdateRate {
         UpdateRate {