diff --git a/components/shared/embedder/input_events.rs b/components/shared/embedder/input_events.rs
index 0268be6dd9c..acaa9afb3ff 100644
--- a/components/shared/embedder/input_events.rs
+++ b/components/shared/embedder/input_events.rs
@@ -61,15 +61,16 @@ pub enum MouseButton {
     Other(u16),
 }
 
-impl From<u16> for MouseButton {
-    fn from(value: u16) -> Self {
+impl<T: Into<u64>> From<T> for MouseButton {
+    fn from(value: T) -> Self {
+        let value = value.into();
         match value {
             0 => MouseButton::Left,
             1 => MouseButton::Middle,
             2 => MouseButton::Right,
             3 => MouseButton::Back,
             4 => MouseButton::Forward,
-            _ => MouseButton::Other(value),
+            _ => MouseButton::Other(value as u16),
         }
     }
 }
diff --git a/components/webdriver_server/actions.rs b/components/webdriver_server/actions.rs
index a5df2e6c523..b18a6eaaf2e 100644
--- a/components/webdriver_server/actions.rs
+++ b/components/webdriver_server/actions.rs
@@ -305,11 +305,10 @@ impl Handler {
             },
         });
 
-        let button = (action.button as u16).into();
         let cmd_msg = WebDriverCommandMsg::MouseButtonAction(
             session.webview_id,
             MouseButtonAction::Down,
-            button,
+            action.button.into(),
             pointer_input_state.x as f32,
             pointer_input_state.y as f32,
         );
@@ -351,11 +350,10 @@ impl Handler {
             },
         });
 
-        let button = (action.button as u16).into();
         let cmd_msg = WebDriverCommandMsg::MouseButtonAction(
             session.webview_id,
             MouseButtonAction::Up,
-            button,
+            action.button.into(),
             pointer_input_state.x as f32,
             pointer_input_state.y as f32,
         );
diff --git a/components/webdriver_server/lib.rs b/components/webdriver_server/lib.rs
index 5e289938f0f..ad5b4e736a9 100644
--- a/components/webdriver_server/lib.rs
+++ b/components/webdriver_server/lib.rs
@@ -23,7 +23,7 @@ use constellation_traits::{EmbedderToConstellationMessage, TraversalDirection};
 use cookie::{CookieBuilder, Expiration};
 use crossbeam_channel::{Receiver, Sender, after, select, unbounded};
 use embedder_traits::{
-    WebDriverCommandMsg, WebDriverCookieError, WebDriverFrameId, WebDriverJSError,
+    MouseButton, WebDriverCommandMsg, WebDriverCookieError, WebDriverFrameId, WebDriverJSError,
     WebDriverJSResult, WebDriverJSValue, WebDriverLoadStatus, WebDriverScriptCommand,
 };
 use euclid::{Rect, Size2D};
@@ -1619,7 +1619,10 @@ impl Handler {
                         InputSourceState::Pointer(PointerInputState::new(&PointerType::Mouse)),
                     );
 
-                    // Steps 8.3 - 8.6
+                    // Step 8.7. Construct a pointer move action.
+                    // Step 8.8. Set a property x to 0 on pointer move action.
+                    // Step 8.9. Set a property y to 0 on pointer move action.
+                    // Step 8.10. Set a property origin to element on pointer move action.
                     let pointer_move_action = PointerMoveAction {
                         duration: None,
                         origin: PointerOrigin::Element(WebElement(element_id)),
@@ -1628,32 +1631,32 @@ impl Handler {
                         ..Default::default()
                     };
 
-                    // Steps 8.7 - 8.8
+                    // Step 8.11. Construct pointer down action.
+                    // Step 8.12. Set a property button to 0 on pointer down action.
                     let pointer_down_action = PointerDownAction {
-                        button: 1,
+                        button: i16::from(MouseButton::Left) as u64,
                         ..Default::default()
                     };
 
-                    // Steps 8.9 - 8.10
+                    // Step 8.13. Construct pointer up action.
+                    // Step 8.14. Set a property button to 0 on pointer up action.
                     let pointer_up_action = PointerUpAction {
-                        button: 1,
+                        button: i16::from(MouseButton::Left) as u64,
                         ..Default::default()
                     };
 
-                    // Step 8.11
+                    // Step 8.16 Dispatch a list of actions with input state,
+                    // actions, session's current browsing context, and actions options.
                     if let Err(error) =
                         self.dispatch_pointermove_action(&id, &pointer_move_action, 0)
                     {
                         return Err(WebDriverError::new(error, ""));
                     }
 
-                    // Steps 8.12
                     self.dispatch_pointerdown_action(&id, &pointer_down_action);
-
-                    // Steps 8.13
                     self.dispatch_pointerup_action(&id, &pointer_up_action);
 
-                    // Step 8.14
+                    // Step 8.17 Remove an input source with input state and input id.
                     self.session_mut()?.input_state_table.remove(&id);
 
                     // Step 13