diff --git a/src/browser/EventManager.zig b/src/browser/EventManager.zig
index 5ed22c45..0307662c 100644
--- a/src/browser/EventManager.zig
+++ b/src/browser/EventManager.zig
@@ -83,12 +83,14 @@ pub fn register(self: *EventManager, target: *EventTarget, typ: []const u8, call
         var node = gop.value_ptr.*.first;
         while (node) |n| {
             const listener: *Listener = @alignCast(@fieldParentPtr("node", n));
-            const is_duplicate = switch (callback) {
-                .object => |obj| listener.function.eqlObject(obj),
-                .function => |func| listener.function.eqlFunction(func),
-            };
-            if (is_duplicate and listener.capture == opts.capture) {
-                return;
+            if (listener.typ.eqlSlice(typ)) {
+                const is_duplicate = switch (callback) {
+                    .object => |obj| listener.function.eqlObject(obj),
+                    .function => |func| listener.function.eqlFunction(func),
+                };
+                if (is_duplicate and listener.capture == opts.capture) {
+                    return;
+                }
             }
             node = n.next;
         }
@@ -132,6 +134,7 @@ pub fn dispatch(self: *EventManager, target: *EventTarget, event: *Event) !void
     }
 
     event._target = target;
+    event._dispatch_target = target; // Store original target for composedPath()
     var was_handled = false;
 
     defer if (was_handled) {
@@ -173,6 +176,7 @@ pub fn dispatchWithFunction(self: *EventManager, target: *EventTarget, event: *E
 
     if (comptime opts.inject_target) {
         event._target = target;
+        event._dispatch_target = target; // Store original target for composedPath()
     }
 
     var was_dispatched = false;
diff --git a/src/browser/Page.zig b/src/browser/Page.zig
index 58b63dfb..48efcb44 100644
--- a/src/browser/Page.zig
+++ b/src/browser/Page.zig
@@ -503,7 +503,7 @@ pub fn documentIsLoaded(self: *Page) void {
 }
 
 pub fn _documentIsLoaded(self: *Page) !void {
-    const event = try Event.init("DOMContentLoaded", .{ .bubbles = true }, self);
+    const event = try Event.initTrusted("DOMContentLoaded", .{ .bubbles = true }, self);
     try self._event_manager.dispatch(
         self.document.asEventTarget(),
         event,
@@ -549,7 +549,7 @@ fn _documentIsComplete(self: *Page) !void {
     self.document._ready_state = .complete;
 
     // dispatch window.load event
-    const event = try Event.init("load", .{}, self);
+    const event = try Event.initTrusted("load", .{}, self);
     // this event is weird, it's dispatched directly on the window, but
     // with the document as the target
     event._target = self.document.asEventTarget();
@@ -560,7 +560,7 @@ fn _documentIsComplete(self: *Page) !void {
         .{ .inject_target = false, .context = "page load" },
     );
 
-    const pageshow_event = try PageTransitionEvent.init("pageshow", .{}, self);
+    const pageshow_event = try PageTransitionEvent.initTrusted("pageshow", .{}, self);
     try self._event_manager.dispatchWithFunction(
         self.window.asEventTarget(),
         pageshow_event.asEvent(),
@@ -1174,7 +1174,7 @@ pub fn deliverSlotchangeEvents(self: *Page) void {
     self._slots_pending_slotchange.clearRetainingCapacity();
 
     for (slots) |slot| {
-        const event = Event.init("slotchange", .{ .bubbles = true }, self) catch |err| {
+        const event = Event.initTrusted("slotchange", .{ .bubbles = true }, self) catch |err| {
             log.err(.page, "deliverSlotchange.init", .{ .err = err });
             continue;
         };
@@ -2419,6 +2419,7 @@ pub fn triggerMouseClick(self: *Page, x: f64, y: f64) !void {
     const event = try @import("webapi/event/MouseEvent.zig").init("click", .{
         .bubbles = true,
         .cancelable = true,
+        .composed = true,
         .clientX = x,
         .clientY = y,
     }, self);
diff --git a/src/browser/ScriptManager.zig b/src/browser/ScriptManager.zig
index 363e1fa1..1936f390 100644
--- a/src/browser/ScriptManager.zig
+++ b/src/browser/ScriptManager.zig
@@ -833,7 +833,7 @@ pub const Script = struct {
         const cb = cb_ orelse return;
 
         const Event = @import("webapi/Event.zig");
-        const event = Event.init(typ, .{}, page) catch |err| {
+        const event = Event.initTrusted(typ, .{}, page) catch |err| {
             log.warn(.js, "script internal callback", .{
                 .url = self.url,
                 .type = typ,
diff --git a/src/browser/tests/event/keyboard.html b/src/browser/tests/event/keyboard.html
index 54419903..b6c3ddd8 100644
--- a/src/browser/tests/event/keyboard.html
+++ b/src/browser/tests/event/keyboard.html
@@ -88,3 +88,18 @@
 
   testing.expectEqual(true, isKeyPress);
 </script>
+
+<script id=isTrusted>
+  // Test isTrusted on KeyboardEvent
+  let keyEvent = new KeyboardEvent('keydown', {key: 'a'});
+  testing.expectEqual(false, keyEvent.isTrusted);
+
+  // Test isTrusted on dispatched KeyboardEvent
+  let keyIsTrusted = null;
+  document.addEventListener('keytest', (e) => {
+    keyIsTrusted = e.isTrusted;
+    testing.expectEqual(true, e instanceof KeyboardEvent);
+  });
+  document.dispatchEvent(new KeyboardEvent('keytest', {key: 'b'}));
+  testing.expectEqual(false, keyIsTrusted);
+</script>
diff --git a/src/browser/tests/event/mouse.html b/src/browser/tests/event/mouse.html
index 4f8dd17f..896ba62b 100644
--- a/src/browser/tests/event/mouse.html
+++ b/src/browser/tests/event/mouse.html
@@ -35,3 +35,18 @@
   testing.expectEqual('click', evt.type);
   testing.expectEqual(true, evt instanceof MouseEvent);
 </script>
+
+<script id=isTrusted>
+  // Test isTrusted on MouseEvent
+  let mouseEvent = new MouseEvent('click');
+  testing.expectEqual(false, mouseEvent.isTrusted);
+
+  // Test isTrusted on dispatched MouseEvent
+  let mouseIsTrusted = null;
+  document.addEventListener('mousetest', (e) => {
+    mouseIsTrusted = e.isTrusted;
+    testing.expectEqual(true, e instanceof MouseEvent);
+  });
+  document.dispatchEvent(new MouseEvent('mousetest'));
+  testing.expectEqual(false, mouseIsTrusted);
+</script>
diff --git a/src/browser/tests/events.html b/src/browser/tests/events.html
index 84300217..a6706847 100644
--- a/src/browser/tests/events.html
+++ b/src/browser/tests/events.html
@@ -612,3 +612,21 @@
     content.dispatchEvent(new Event('he2'));
   }
 </script>
+
+<script id=isTrusted>
+  // Test isTrusted property on generic Event
+  let untrustedEvent = new Event('test');
+  testing.expectEqual(false, untrustedEvent.isTrusted);
+
+  // Test isTrusted on dispatched events
+  let isTrustedValue = null;
+  document.addEventListener('trusttest', (e) => {
+    isTrustedValue = e.isTrusted;
+  });
+  document.dispatchEvent(new Event('trusttest'));
+  testing.expectEqual(false, isTrustedValue);
+
+  // Test isTrusted with bubbling events
+  let bubbledEvent = new Event('bubble', {bubbles: true});
+  testing.expectEqual(false, bubbledEvent.isTrusted);
+</script>
diff --git a/src/browser/tests/legacy/events/event.html b/src/browser/tests/legacy/events/event.html
index 752d64ba..a24cfbdb 100644
--- a/src/browser/tests/legacy/events/event.html
+++ b/src/browser/tests/legacy/events/event.html
@@ -27,7 +27,7 @@
   testing.expectEqual(true, evt.bubbles);
   testing.expectEqual(true, evt.cancelable);
   testing.expectEqual(true, evt.defaultPrevented);
-  testing.expectEqual(true, evt.isTrusted);
+  testing.expectEqual(false, evt.isTrusted);
   testing.expectEqual(true, evt.timeStamp >= Math.floor(startTime));
 </script>
 
diff --git a/src/browser/tests/shadowroot/events.html b/src/browser/tests/shadowroot/events.html
index de6f7cdc..c0832f21 100644
--- a/src/browser/tests/shadowroot/events.html
+++ b/src/browser/tests/shadowroot/events.html
@@ -184,3 +184,100 @@
     host.remove();
 }
 </script>
+
+<script id="composedPath_open_shadow_from_host">
+{
+    // Test that open shadow root exposes internals in composedPath
+    const host = document.createElement('div');
+    const shadow = host.attachShadow({ mode: 'open' });
+    const button = document.createElement('button');
+
+    shadow.appendChild(button);
+    document.body.appendChild(host);
+
+    let capturedPath = null;
+
+    host.addEventListener('click', (e) => {
+        capturedPath = e.composedPath();
+    });
+
+    const event = new Event('click', { bubbles: true, composed: true });
+    button.dispatchEvent(event);
+
+    // Open shadow: external listener should see shadow internals
+    testing.expectEqual(7, capturedPath.length);
+    testing.expectEqual(button, capturedPath[0]);
+    testing.expectEqual(shadow, capturedPath[1]);
+    testing.expectEqual(host, capturedPath[2]);
+    testing.expectEqual(document.body, capturedPath[3]);
+    testing.expectEqual(document.documentElement, capturedPath[4]);
+    testing.expectEqual(document, capturedPath[5]);
+    testing.expectEqual(window, capturedPath[6]);
+
+    host.remove();
+}
+</script>
+
+<script id="composedPath_closed_shadow_from_host">
+{
+    // Test that closed shadow root hides internals in composedPath
+    const host = document.createElement('div');
+    const shadow = host.attachShadow({ mode: 'closed' });
+    const button = document.createElement('button');
+
+    shadow.appendChild(button);
+    document.body.appendChild(host);
+
+    let capturedPath = null;
+
+    host.addEventListener('click', (e) => {
+        capturedPath = e.composedPath();
+    });
+
+    const event = new Event('click', { bubbles: true, composed: true });
+    button.dispatchEvent(event);
+
+    // Closed shadow: external listener should NOT see shadow internals
+    testing.expectEqual(5, capturedPath.length);
+    testing.expectEqual(host, capturedPath[0]);
+    testing.expectEqual(document.body, capturedPath[1]);
+    testing.expectEqual(document.documentElement, capturedPath[2]);
+    testing.expectEqual(document, capturedPath[3]);
+    testing.expectEqual(window, capturedPath[4]);
+
+    host.remove();
+}
+</script>
+
+<script id="composedPath_closed_shadow_from_inside">
+{
+    // Test that closed shadow root still exposes internals to internal listeners
+    const host = document.createElement('div');
+    const shadow = host.attachShadow({ mode: 'closed' });
+    const button = document.createElement('button');
+
+    shadow.appendChild(button);
+    document.body.appendChild(host);
+
+    let capturedPath = null;
+
+    button.addEventListener('click', (e) => {
+        capturedPath = e.composedPath();
+    });
+
+    const event = new Event('click', { bubbles: true, composed: true });
+    button.dispatchEvent(event);
+
+    // Inside the shadow: should see full path including shadow internals
+    testing.expectEqual(7, capturedPath.length);
+    testing.expectEqual(button, capturedPath[0]);
+    testing.expectEqual(shadow, capturedPath[1]);
+    testing.expectEqual(host, capturedPath[2]);
+    testing.expectEqual(document.body, capturedPath[3]);
+    testing.expectEqual(document.documentElement, capturedPath[4]);
+    testing.expectEqual(document, capturedPath[5]);
+    testing.expectEqual(window, capturedPath[6]);
+
+    host.remove();
+}
+</script>
diff --git a/src/browser/webapi/AbortSignal.zig b/src/browser/webapi/AbortSignal.zig
index 9d01ef64..c4b0f7ed 100644
--- a/src/browser/webapi/AbortSignal.zig
+++ b/src/browser/webapi/AbortSignal.zig
@@ -80,7 +80,7 @@ pub fn abort(self: *AbortSignal, reason_: ?Reason, page: *Page) !void {
     }
 
     // Dispatch abort event
-    const event = try Event.init("abort", .{}, page);
+    const event = try Event.initTrusted("abort", .{}, page);
     try page._event_manager.dispatchWithFunction(
         self.asEventTarget(),
         event,
diff --git a/src/browser/webapi/Document.zig b/src/browser/webapi/Document.zig
index a4d20ed1..70289a37 100644
--- a/src/browser/webapi/Document.zig
+++ b/src/browser/webapi/Document.zig
@@ -251,7 +251,7 @@ pub fn createTextNode(_: *const Document, data: []const u8, page: *Page) !*Node
 
 pub fn createCDATASection(self: *const Document, data: []const u8, page: *Page) !*Node {
     switch (self._type) {
-        .html => return error.NotSupported,  // cannot create a CDataSection in an HTMLDocument
+        .html => return error.NotSupported, // cannot create a CDataSection in an HTMLDocument
         .xml => return page.createCDATASection(data),
         .generic => return page.createCDATASection(data),
     }
@@ -570,7 +570,7 @@ pub fn getChildElementCount(self: *Document) u32 {
     return i;
 }
 
- pub fn getAdoptedStyleSheets(self: *Document, page: *Page) !js.Object {
+pub fn getAdoptedStyleSheets(self: *Document, page: *Page) !js.Object {
     if (self._adopted_style_sheets) |ass| {
         return ass;
     }
diff --git a/src/browser/webapi/Element.zig b/src/browser/webapi/Element.zig
index 0fbf547f..a3c8ed0e 100644
--- a/src/browser/webapi/Element.zig
+++ b/src/browser/webapi/Element.zig
@@ -596,7 +596,7 @@ pub fn focus(self: *Element, page: *Page) !void {
             return;
         }
 
-        const blur_event = try Event.init("blur", null, page);
+        const blur_event = try Event.initTrusted("blur", null, page);
         try page._event_manager.dispatch(old.asEventTarget(), blur_event);
     }
 
@@ -604,7 +604,7 @@ pub fn focus(self: *Element, page: *Page) !void {
         page.document._active_element = self;
     }
 
-    const focus_event = try Event.init("focus", null, page);
+    const focus_event = try Event.initTrusted("focus", null, page);
     try page._event_manager.dispatch(self.asEventTarget(), focus_event);
 }
 
@@ -614,7 +614,7 @@ pub fn blur(self: *Element, page: *Page) !void {
     page.document._active_element = null;
 
     const Event = @import("Event.zig");
-    const blur_event = try Event.init("blur", null, page);
+    const blur_event = try Event.initTrusted("blur", null, page);
     try page._event_manager.dispatch(self.asEventTarget(), blur_event);
 }
 
diff --git a/src/browser/webapi/Event.zig b/src/browser/webapi/Event.zig
index 7aa14cff..f32f21ab 100644
--- a/src/browser/webapi/Event.zig
+++ b/src/browser/webapi/Event.zig
@@ -35,12 +35,14 @@ _composed: bool = false,
 _type_string: String,
 _target: ?*EventTarget = null,
 _current_target: ?*EventTarget = null,
+_dispatch_target: ?*EventTarget = null, // Original target for composedPath()
 _prevent_default: bool = false,
 _stop_propagation: bool = false,
 _stop_immediate_propagation: bool = false,
 _event_phase: EventPhase = .none,
 _time_stamp: u64 = 0,
 _needs_retargeting: bool = false,
+_isTrusted: bool = false,
 
 pub const EventPhase = enum(u8) {
     none = 0,
@@ -68,14 +70,22 @@ pub const Options = struct {
     composed: bool = false,
 };
 
+pub fn initTrusted(typ: []const u8, opts_: ?Options, page: *Page) !*Event {
+    return initWithTrusted(typ, opts_, true, page);
+}
+
 pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*Event {
+    return initWithTrusted(typ, opts_, false, page);
+}
+
+fn initWithTrusted(typ: []const u8, opts_: ?Options, trusted: bool, page: *Page) !*Event {
     const opts = opts_ orelse Options{};
 
     // Round to 2ms for privacy (browsers do this)
     const raw_timestamp = @import("../../datetime.zig").milliTimestamp(.monotonic);
     const time_stamp = (raw_timestamp / 2) * 2;
 
-    return page._factory.create(Event{
+    const event = try page._factory.create(Event{
         ._type = .generic,
         ._bubbles = opts.bubbles,
         ._time_stamp = time_stamp,
@@ -83,6 +93,21 @@ pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*Event {
         ._composed = opts.composed,
         ._type_string = try String.init(page.arena, typ, .{}),
     });
+
+    event._isTrusted = trusted;
+    return event;
+}
+
+pub fn initEvent(
+    self: *Event,
+    event_string: []const u8,
+    bubbles: ?bool,
+    cancelable: ?bool,
+    page: *Page,
+) !void {
+    self._type_string = try String.init(page.arena, event_string, .{});
+    self._bubbles = bubbles orelse false;
+    self._cancelable = cancelable orelse false;
 }
 
 pub fn as(self: *Event, comptime T: type) *T {
@@ -159,14 +184,27 @@ pub fn getTimeStamp(self: *const Event) u64 {
     return self._time_stamp;
 }
 
+pub fn setTrusted(self: *Event) void {
+    self._isTrusted = true;
+}
+
+pub fn setUntrusted(self: *Event) void {
+    self._isTrusted = false;
+}
+
+pub fn getIsTrusted(self: *const Event) bool {
+    return self._isTrusted;
+}
+
 pub fn composedPath(self: *Event, page: *Page) ![]const *EventTarget {
     // Return empty array if event is not being dispatched
     if (self._event_phase == .none) {
         return &.{};
     }
 
-    // If there's no target, return empty array
-    const target = self._target orelse return &.{};
+    // Use dispatch_target (original target) if available, otherwise fall back to target
+    // This is important because _target gets retargeted during event dispatch
+    const target = self._dispatch_target orelse self._target orelse return &.{};
 
     // Only nodes have a propagation path
     const target_node = switch (target._type) {
@@ -179,6 +217,9 @@ pub fn composedPath(self: *Event, page: *Page) ![]const *EventTarget {
     var path_buffer: [128]*EventTarget = undefined;
     var stopped_at_shadow_boundary = false;
 
+    // Track closed shadow boundaries (position in path and host position)
+    var closed_shadow_boundary: ?struct { shadow_end: usize, host_start: usize } = null;
+
     var node: ?*Node = target_node;
     while (node) |n| {
         if (path_len >= path_buffer.len) {
@@ -198,7 +239,17 @@ pub fn composedPath(self: *Event, page: *Page) ![]const *EventTarget {
                     break;
                 }
 
-                // Otherwise, jump to the shadow host and continue
+                // Track the first closed shadow boundary we encounter
+                if (shadow._mode == .closed and closed_shadow_boundary == null) {
+                    // Mark where the shadow root is in the path
+                    // The next element will be the host
+                    closed_shadow_boundary = .{
+                        .shadow_end = path_len - 1, // index of shadow root
+                        .host_start = path_len, // index where host will be
+                    };
+                }
+
+                // Jump to the shadow host and continue
                 node = shadow._host.asNode();
                 continue;
             }
@@ -215,9 +266,40 @@ pub fn composedPath(self: *Event, page: *Page) ![]const *EventTarget {
         }
     }
 
-    // Allocate and return the path using call_arena (short-lived)
-    const path = try page.call_arena.alloc(*EventTarget, path_len);
-    @memcpy(path, path_buffer[0..path_len]);
+    // Determine visible path based on current_target and closed shadow boundaries
+    var visible_start_index: usize = 0;
+
+    if (closed_shadow_boundary) |boundary| {
+        // Check if current_target is outside the closed shadow
+        // If current_target is null or is at/after the host position, hide shadow internals
+        const current_target = self._current_target;
+
+        if (current_target) |ct| {
+            // Find current_target in the path
+            var ct_index: ?usize = null;
+            for (path_buffer[0..path_len], 0..) |elem, i| {
+                if (elem == ct) {
+                    ct_index = i;
+                    break;
+                }
+            }
+
+            // If current_target is at or after the host (outside the closed shadow),
+            // hide everything from target up to the host
+            if (ct_index) |idx| {
+                if (idx >= boundary.host_start) {
+                    visible_start_index = boundary.host_start;
+                }
+            }
+        }
+    }
+
+    // Calculate the visible portion of the path
+    const visible_path_len = if (path_len > visible_start_index) path_len - visible_start_index else 0;
+
+    // Allocate and return the visible path using call_arena (short-lived)
+    const path = try page.call_arena.alloc(*EventTarget, visible_path_len);
+    @memcpy(path, path_buffer[visible_start_index..path_len]);
     return path;
 }
 
@@ -257,16 +339,21 @@ pub fn inheritOptions(comptime T: type, comptime additions: anytype) type {
     });
 }
 
-pub fn populatePrototypes(self: anytype, opts: anytype) void {
+pub fn populatePrototypes(self: anytype, opts: anytype, trusted: bool) void {
     const T = @TypeOf(self.*);
 
     if (@hasField(T, "_proto")) {
-        populatePrototypes(self._proto, opts);
+        populatePrototypes(self._proto, opts, trusted);
     }
 
     if (@hasDecl(T, "populateFromOptions")) {
         T.populateFromOptions(self, opts);
     }
+
+    // Set isTrusted at the Event level (base of prototype chain)
+    if (T == Event or @hasField(T, "_isTrusted")) {
+        self._isTrusted = trusted;
+    }
 }
 
 pub const JsApi = struct {
@@ -289,10 +376,12 @@ pub const JsApi = struct {
     pub const eventPhase = bridge.accessor(Event.getEventPhase, null, .{});
     pub const defaultPrevented = bridge.accessor(Event.getDefaultPrevented, null, .{});
     pub const timeStamp = bridge.accessor(Event.getTimeStamp, null, .{});
+    pub const isTrusted = bridge.accessor(Event.getIsTrusted, null, .{});
     pub const preventDefault = bridge.function(Event.preventDefault, .{});
     pub const stopPropagation = bridge.function(Event.stopPropagation, .{});
     pub const stopImmediatePropagation = bridge.function(Event.stopImmediatePropagation, .{});
     pub const composedPath = bridge.function(Event.composedPath, .{});
+    pub const initEvent = bridge.function(Event.initEvent, .{});
 
     // Event phase constants
     pub const NONE = bridge.property(@intFromEnum(EventPhase.none));
diff --git a/src/browser/webapi/History.zig b/src/browser/webapi/History.zig
index 9511e4d4..5ff5c860 100644
--- a/src/browser/webapi/History.zig
+++ b/src/browser/webapi/History.zig
@@ -79,7 +79,7 @@ fn goInner(delta: i32, page: *Page) !void {
 
     if (entry._url) |url| {
         if (try page.isSameOrigin(url)) {
-            const event = try PopStateEvent.init("popstate", .{ .state = entry._state.value }, page);
+            const event = try PopStateEvent.initTrusted("popstate", .{ .state = entry._state.value }, page);
 
             try page._event_manager.dispatchWithFunction(
                 page.window.asEventTarget(),
diff --git a/src/browser/webapi/MessagePort.zig b/src/browser/webapi/MessagePort.zig
index 4d72a934..ea6e79ca 100644
--- a/src/browser/webapi/MessagePort.zig
+++ b/src/browser/webapi/MessagePort.zig
@@ -129,7 +129,7 @@ const PostMessageCallback = struct {
             return null;
         }
 
-        const event = MessageEvent.init("message", .{
+        const event = MessageEvent.initTrusted("message", .{
             .data = self.message,
             .origin = "",
             .source = null,
diff --git a/src/browser/webapi/Range.zig b/src/browser/webapi/Range.zig
index 8f220e67..feca23c4 100644
--- a/src/browser/webapi/Range.zig
+++ b/src/browser/webapi/Range.zig
@@ -33,7 +33,7 @@ pub fn asAbstractRange(self: *Range) *AbstractRange {
 }
 
 pub fn init(page: *Page) !*Range {
-    return page._factory.abstractRange(Range{._proto = undefined}, page);
+    return page._factory.abstractRange(Range{ ._proto = undefined }, page);
 }
 
 pub fn setStart(self: *Range, node: *Node, offset: u32) !void {
@@ -106,7 +106,7 @@ pub fn collapse(self: *Range, to_start: ?bool) void {
 }
 
 pub fn cloneRange(self: *const Range, page: *Page) !*Range {
-    const clone = try page._factory.abstractRange(Range{._proto = undefined}, page);
+    const clone = try page._factory.abstractRange(Range{ ._proto = undefined }, page);
     clone._proto._end_offset = self._proto._end_offset;
     clone._proto._start_offset = self._proto._start_offset;
     clone._proto._end_container = self._proto._end_container;
diff --git a/src/browser/webapi/Window.zig b/src/browser/webapi/Window.zig
index 1fcfec80..2aaff9f7 100644
--- a/src/browser/webapi/Window.zig
+++ b/src/browser/webapi/Window.zig
@@ -270,7 +270,7 @@ pub fn cancelIdleCallback(self: *Window, id: u32) void {
 }
 
 pub fn reportError(self: *Window, err: js.Object, page: *Page) !void {
-    const error_event = try ErrorEvent.init("error", .{
+    const error_event = try ErrorEvent.initTrusted("error", .{
         .@"error" = err,
         .message = err.toString() catch "Unknown error",
         .bubbles = false,
@@ -410,7 +410,7 @@ pub fn scrollTo(self: *Window, opts: ScrollToOpts, y: ?i32, page: *Page) !void {
                     return null;
                 }
 
-                const event = try Event.init("scroll", .{ .bubbles = true }, p);
+                const event = try Event.initTrusted("scroll", .{ .bubbles = true }, p);
                 try p._event_manager.dispatch(p.document.asEventTarget(), event);
 
                 pos.state = .end;
@@ -437,7 +437,7 @@ pub fn scrollTo(self: *Window, opts: ScrollToOpts, y: ?i32, page: *Page) !void {
                     .end => {},
                     .done => return null,
                 }
-                const event = try Event.init("scrollend", .{ .bubbles = true }, p);
+                const event = try Event.initTrusted("scrollend", .{ .bubbles = true }, p);
                 try p._event_manager.dispatch(p.document.asEventTarget(), event);
 
                 pos.state = .done;
@@ -586,7 +586,7 @@ const PostMessageCallback = struct {
         const self: *PostMessageCallback = @ptrCast(@alignCast(ctx));
         defer self.deinit();
 
-        const message_event = try MessageEvent.init("message", .{
+        const message_event = try MessageEvent.initTrusted("message", .{
             .data = self.message,
             .origin = self.origin,
             .source = self.window,
diff --git a/src/browser/webapi/element/Html.zig b/src/browser/webapi/element/Html.zig
index 8de457b6..fc033441 100644
--- a/src/browser/webapi/element/Html.zig
+++ b/src/browser/webapi/element/Html.zig
@@ -306,6 +306,7 @@ pub fn click(self: *HtmlElement, page: *Page) !void {
     const event = try @import("../event/MouseEvent.zig").init("click", .{
         .bubbles = true,
         .cancelable = true,
+        .composed = true,
         .clientX = 0,
         .clientY = 0,
     }, page);
diff --git a/src/browser/webapi/event/CompositionEvent.zig b/src/browser/webapi/event/CompositionEvent.zig
index a758c621..f77489dc 100644
--- a/src/browser/webapi/event/CompositionEvent.zig
+++ b/src/browser/webapi/event/CompositionEvent.zig
@@ -40,7 +40,7 @@ pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*CompositionEvent {
         ._data = if (opts.data) |str| try page.dupeString(str) else "",
     });
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, false);
     return event;
 }
 
diff --git a/src/browser/webapi/event/CustomEvent.zig b/src/browser/webapi/event/CustomEvent.zig
index 6456b6cf..55f6b87c 100644
--- a/src/browser/webapi/event/CustomEvent.zig
+++ b/src/browser/webapi/event/CustomEvent.zig
@@ -49,23 +49,23 @@ pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*CustomEvent {
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, false);
     return event;
 }
 
- pub fn initCustomEvent(
+pub fn initCustomEvent(
     self: *CustomEvent,
     event_string: []const u8,
-    bubbles: bool,
-    cancelable: bool,
+    bubbles: ?bool,
+    cancelable: ?bool,
     detail_: ?js.Object,
     page: *Page,
 ) !void {
     // This function can only be called after the constructor has called.
     // So we assume proto is initialized already by constructor.
     self._proto._type_string = try String.init(page.arena, event_string, .{});
-    self._proto._bubbles = bubbles;
-    self._proto._cancelable = cancelable;
+    self._proto._bubbles = bubbles orelse false;
+    self._proto._cancelable = cancelable orelse false;
     // Detail is stored separately.
     if (detail_) |detail| {
         self._detail = try detail.persist();
diff --git a/src/browser/webapi/event/ErrorEvent.zig b/src/browser/webapi/event/ErrorEvent.zig
index 08124d7f..25e2e787 100644
--- a/src/browser/webapi/event/ErrorEvent.zig
+++ b/src/browser/webapi/event/ErrorEvent.zig
@@ -44,6 +44,14 @@ pub const ErrorEventOptions = struct {
 const Options = Event.inheritOptions(ErrorEvent, ErrorEventOptions);
 
 pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*ErrorEvent {
+    return initWithTrusted(typ, opts_, false, page);
+}
+
+pub fn initTrusted(typ: []const u8, opts_: ?Options, page: *Page) !*ErrorEvent {
+    return initWithTrusted(typ, opts_, true, page);
+}
+
+fn initWithTrusted(typ: []const u8, opts_: ?Options, trusted: bool, page: *Page) !*ErrorEvent {
     const arena = page.arena;
     const opts = opts_ orelse Options{};
 
@@ -60,7 +68,7 @@ pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*ErrorEvent {
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, trusted);
     return event;
 }
 
diff --git a/src/browser/webapi/event/KeyboardEvent.zig b/src/browser/webapi/event/KeyboardEvent.zig
index eaa04e64..d0f47d23 100644
--- a/src/browser/webapi/event/KeyboardEvent.zig
+++ b/src/browser/webapi/event/KeyboardEvent.zig
@@ -182,7 +182,15 @@ const Options = Event.inheritOptions(
     KeyboardEventOptions,
 );
 
+pub fn initTrusted(typ: []const u8, _opts: ?Options, page: *Page) !*KeyboardEvent {
+    return initWithTrusted(typ, _opts, true, page);
+}
+
 pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*KeyboardEvent {
+    return initWithTrusted(typ, _opts, false, page);
+}
+
+fn initWithTrusted(typ: []const u8, _opts: ?Options, trusted: bool, page: *Page) !*KeyboardEvent {
     const opts = _opts orelse Options{};
 
     const event = try page._factory.uiEvent(
@@ -201,7 +209,7 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*KeyboardEvent {
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, trusted);
     return event;
 }
 
diff --git a/src/browser/webapi/event/MessageEvent.zig b/src/browser/webapi/event/MessageEvent.zig
index 9f24c517..086bb0e5 100644
--- a/src/browser/webapi/event/MessageEvent.zig
+++ b/src/browser/webapi/event/MessageEvent.zig
@@ -38,6 +38,14 @@ const MessageEventOptions = struct {
 const Options = Event.inheritOptions(MessageEvent, MessageEventOptions);
 
 pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*MessageEvent {
+    return initWithTrusted(typ, opts_, false, page);
+}
+
+pub fn initTrusted(typ: []const u8, opts_: ?Options, page: *Page) !*MessageEvent {
+    return initWithTrusted(typ, opts_, true, page);
+}
+
+fn initWithTrusted(typ: []const u8, opts_: ?Options, trusted: bool, page: *Page) !*MessageEvent {
     const opts = opts_ orelse Options{};
 
     const event = try page._factory.event(
@@ -50,7 +58,7 @@ pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*MessageEvent {
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, trusted);
     return event;
 }
 
diff --git a/src/browser/webapi/event/MouseEvent.zig b/src/browser/webapi/event/MouseEvent.zig
index 50d5f879..977034cf 100644
--- a/src/browser/webapi/event/MouseEvent.zig
+++ b/src/browser/webapi/event/MouseEvent.zig
@@ -88,7 +88,7 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*MouseEvent {
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, false);
     return event;
 }
 
diff --git a/src/browser/webapi/event/NavigationCurrentEntryChangeEvent.zig b/src/browser/webapi/event/NavigationCurrentEntryChangeEvent.zig
index 40c8122a..b22e32f0 100644
--- a/src/browser/webapi/event/NavigationCurrentEntryChangeEvent.zig
+++ b/src/browser/webapi/event/NavigationCurrentEntryChangeEvent.zig
@@ -40,9 +40,18 @@ const Options = Event.inheritOptions(
     NavigationCurrentEntryChangeEventOptions,
 );
 
-pub fn init(
+pub fn init(typ: []const u8, opts: Options, page: *Page) !*NavigationCurrentEntryChangeEvent {
+    return initWithTrusted(typ, opts, false, page);
+}
+
+pub fn initTrusted(typ: []const u8, opts: Options, page: *Page) !*NavigationCurrentEntryChangeEvent {
+    return initWithTrusted(typ, opts, true, page);
+}
+
+fn initWithTrusted(
     typ: []const u8,
     opts: Options,
+    trusted: bool,
     page: *Page,
 ) !*NavigationCurrentEntryChangeEvent {
     const navigation_type = if (opts.navigationType) |nav_type_str|
@@ -59,7 +68,7 @@ pub fn init(
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, trusted);
     return event;
 }
 
diff --git a/src/browser/webapi/event/PageTransitionEvent.zig b/src/browser/webapi/event/PageTransitionEvent.zig
index 2b7d063f..37b7edf1 100644
--- a/src/browser/webapi/event/PageTransitionEvent.zig
+++ b/src/browser/webapi/event/PageTransitionEvent.zig
@@ -35,6 +35,14 @@ const PageTransitionEventOptions = struct {
 const Options = Event.inheritOptions(PageTransitionEvent, PageTransitionEventOptions);
 
 pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*PageTransitionEvent {
+    return initWithTrusted(typ, _opts, false, page);
+}
+
+pub fn initTrusted(typ: []const u8, _opts: ?Options, page: *Page) !*PageTransitionEvent {
+    return initWithTrusted(typ, _opts, true, page);
+}
+
+fn initWithTrusted(typ: []const u8, _opts: ?Options, trusted: bool, page: *Page) !*PageTransitionEvent {
     const opts = _opts orelse Options{};
 
     const event = try page._factory.event(
@@ -45,7 +53,7 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*PageTransitionEvent
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, trusted);
     return event;
 }
 
diff --git a/src/browser/webapi/event/PopStateEvent.zig b/src/browser/webapi/event/PopStateEvent.zig
index 45a088c5..305ef5cc 100644
--- a/src/browser/webapi/event/PopStateEvent.zig
+++ b/src/browser/webapi/event/PopStateEvent.zig
@@ -35,6 +35,14 @@ const PopStateEventOptions = struct {
 const Options = Event.inheritOptions(PopStateEvent, PopStateEventOptions);
 
 pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*PopStateEvent {
+    return initWithTrusted(typ, _opts, false, page);
+}
+
+pub fn initTrusted(typ: []const u8, _opts: ?Options, page: *Page) !*PopStateEvent {
+    return initWithTrusted(typ, _opts, true, page);
+}
+
+fn initWithTrusted(typ: []const u8, _opts: ?Options, trusted: bool, page: *Page) !*PopStateEvent {
     const opts = _opts orelse Options{};
 
     const event = try page._factory.event(
@@ -45,7 +53,7 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*PopStateEvent {
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, trusted);
     return event;
 }
 
diff --git a/src/browser/webapi/event/ProgressEvent.zig b/src/browser/webapi/event/ProgressEvent.zig
index 8fbfbb87..61fe49c9 100644
--- a/src/browser/webapi/event/ProgressEvent.zig
+++ b/src/browser/webapi/event/ProgressEvent.zig
@@ -34,6 +34,14 @@ const ProgressEventOptions = struct {
 const Options = Event.inheritOptions(ProgressEvent, ProgressEventOptions);
 
 pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*ProgressEvent {
+    return initWithTrusted(typ, _opts, false, page);
+}
+
+pub fn initTrusted(typ: []const u8, _opts: ?Options, page: *Page) !*ProgressEvent {
+    return initWithTrusted(typ, _opts, true, page);
+}
+
+fn initWithTrusted(typ: []const u8, _opts: ?Options, trusted: bool, page: *Page) !*ProgressEvent {
     const opts = _opts orelse Options{};
 
     const event = try page._factory.event(
@@ -45,7 +53,7 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*ProgressEvent {
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, trusted);
     return event;
 }
 
diff --git a/src/browser/webapi/event/UIEvent.zig b/src/browser/webapi/event/UIEvent.zig
index c30e8743..2ea51f7a 100644
--- a/src/browser/webapi/event/UIEvent.zig
+++ b/src/browser/webapi/event/UIEvent.zig
@@ -57,7 +57,7 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*UIEvent {
         },
     );
 
-    Event.populatePrototypes(event, opts);
+    Event.populatePrototypes(event, opts, false);
     return event;
 }
 
diff --git a/src/browser/webapi/navigation/Navigation.zig b/src/browser/webapi/navigation/Navigation.zig
index b1fcb225..e3e38a7b 100644
--- a/src/browser/webapi/navigation/Navigation.zig
+++ b/src/browser/webapi/navigation/Navigation.zig
@@ -201,7 +201,7 @@ pub fn pushEntry(
 
     if (previous) |prev| {
         if (dispatch) {
-            const event = try NavigationCurrentEntryChangeEvent.init(
+            const event = try NavigationCurrentEntryChangeEvent.initTrusted(
                 "currententrychange",
                 .{ .from = prev, .navigationType = @tagName(.push) },
                 page,
@@ -240,7 +240,7 @@ pub fn replaceEntry(
     self._entries.items[self._index] = entry;
 
     if (dispatch) {
-        const event = try NavigationCurrentEntryChangeEvent.init(
+        const event = try NavigationCurrentEntryChangeEvent.initTrusted(
             "currententrychange",
             .{ .from = previous, .navigationType = @tagName(.replace) },
             page,
@@ -324,7 +324,7 @@ pub fn navigateInner(
     }
 
     // If we haven't navigated off, let us fire off an a currententrychange.
-    const event = try NavigationCurrentEntryChangeEvent.init(
+    const event = try NavigationCurrentEntryChangeEvent.initTrusted(
         "currententrychange",
         .{ .from = previous, .navigationType = @tagName(kind) },
         page,
@@ -363,7 +363,7 @@ pub fn reload(self: *Navigation, _opts: ?ReloadOptions, page: *Page) !Navigation
         const previous = entry;
         entry._state = .{ .source = .navigation, .value = state.toJson(arena) catch return error.DataClone };
 
-        const event = try NavigationCurrentEntryChangeEvent.init(
+        const event = try NavigationCurrentEntryChangeEvent.initTrusted(
             "currententrychange",
             .{ .from = previous, .navigationType = @tagName(.reload) },
             page,
@@ -405,7 +405,7 @@ pub fn updateCurrentEntry(self: *Navigation, options: UpdateCurrentEntryOptions,
         .value = options.state.toJson(arena) catch return error.DataClone,
     };
 
-    const event = try NavigationCurrentEntryChangeEvent.init(
+    const event = try NavigationCurrentEntryChangeEvent.initTrusted(
         "currententrychange",
         .{ .from = previous, .navigationType = null },
         page,
diff --git a/src/browser/webapi/net/XMLHttpRequest.zig b/src/browser/webapi/net/XMLHttpRequest.zig
index 0d903249..c3aef7f6 100644
--- a/src/browser/webapi/net/XMLHttpRequest.zig
+++ b/src/browser/webapi/net/XMLHttpRequest.zig
@@ -416,7 +416,7 @@ fn stateChanged(self: *XMLHttpRequest, state: ReadyState, page: *Page) !void {
 
     self._ready_state = state;
 
-    const event = try Event.init("readystatechange", .{}, page);
+    const event = try Event.initTrusted("readystatechange", .{}, page);
     try page._event_manager.dispatchWithFunction(
         self.asEventTarget(),
         event,
diff --git a/src/browser/webapi/net/XMLHttpRequestEventTarget.zig b/src/browser/webapi/net/XMLHttpRequestEventTarget.zig
index af861c74..b8efe47d 100644
--- a/src/browser/webapi/net/XMLHttpRequestEventTarget.zig
+++ b/src/browser/webapi/net/XMLHttpRequestEventTarget.zig
@@ -57,7 +57,7 @@ pub fn dispatch(self: *XMLHttpRequestEventTarget, comptime event_type: DispatchT
     };
 
     const progress = progress_ orelse Progress{};
-    const event = try ProgressEvent.init(
+    const event = try ProgressEvent.initTrusted(
         typ,
         .{ .total = progress.total, .loaded = progress.loaded },
         page,
diff --git a/src/cdp/domains/input.zig b/src/cdp/domains/input.zig
index 388d986b..492e9b9e 100644
--- a/src/cdp/domains/input.zig
+++ b/src/cdp/domains/input.zig
@@ -60,7 +60,7 @@ fn dispatchKeyEvent(cmd: anytype) !void {
     const page = bc.session.currentPage() orelse return;
 
     const KeyboardEvent = @import("../../browser/webapi/event/KeyboardEvent.zig");
-    const keyboard_event = try KeyboardEvent.init("keydown", .{
+    const keyboard_event = try KeyboardEvent.initTrusted("keydown", .{
         .key = params.key,
         .code = params.code,
         .altKey = params.modifiers & 1 == 1,