Merge branch 'main' into semantic-versioning

.github/workflows/e2e-test.yml

@@ -192,13 +192,15 @@ jobs:
 
       - run: chmod a+x ./lightpanda
 
+      # force a wakup of the auth server before requesting it w/ the test itself
+      - run: curl https://${{ vars.WBA_DOMAIN }}
+
       - name: run wba test
         shell: bash
         run: |
-
           node webbotauth/validator.js &
           VALIDATOR_PID=$!
-          sleep 2
+          sleep 5
 
           exec 3<<< "${{ secrets.WBA_PRIVATE_KEY_PEM }}"
 

.github/workflows/wpt.yml

@@ -10,7 +10,7 @@ env:
 
 on:
   schedule:
-    - cron: "23 2 * * *"
+    - cron: "21 2 * * *"
 
   # Allows you to run this workflow manually from the Actions tab
   workflow_dispatch:
@@ -19,8 +19,12 @@ jobs:
   wpt-build-release:
     name: zig build release
 
-    runs-on: ubuntu-latest
+    env:
-    timeout-minutes: 15
+      ARCH: aarch64
+      OS: linux
+
+    runs-on: ubuntu-24.04-arm
+    timeout-minutes: 20
 
     steps:
       - uses: actions/checkout@v6
@@ -28,9 +32,15 @@ jobs:
           fetch-depth: 0
 
       - uses: ./.github/actions/install
+        with:
+          os: ${{env.OS}}
+          arch: ${{env.ARCH}}
+
+      - name: v8 snapshot
+        run: zig build -Dprebuilt_v8_path=v8/libc_v8.a -Doptimize=ReleaseFast snapshot_creator -- src/snapshot.bin
 
       - name: zig build release
-        run: zig build -Dprebuilt_v8_path=v8/libc_v8.a -Doptimize=ReleaseFast -Dcpu=x86_64
+        run: zig build -Dsnapshot_path=../../snapshot.bin -Dprebuilt_v8_path=v8/libc_v8.a -Doptimize=ReleaseFast -Dcpu=generic
 
       - name: upload artifact
         uses: actions/upload-artifact@v7
@@ -43,7 +53,7 @@ jobs:
   wpt-build-runner:
     name: build wpt runner
 
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-24.04-arm
     timeout-minutes: 15
 
     steps:
@@ -71,8 +81,8 @@ jobs:
       - wpt-build-runner
 
     # use a self host runner.
-    runs-on: lpd-bench-hetzner
+    runs-on: lpd-wpt-aws
-    timeout-minutes: 180
+    timeout-minutes: 600
 
     steps:
       - uses: actions/checkout@v6
@@ -105,8 +115,8 @@ jobs:
       - name: run test with json output
         run: |
           ./wpt serve 2> /dev/null & echo $! > WPT.pid
-          sleep 10s
+          sleep 20s
-          ./wptrunner -lpd-path ./lightpanda -json -concurrency 10 -pool 3 > wpt.json
+          ./wptrunner -lpd-path ./lightpanda -json -concurrency 5 -pool 5 --mem-limit 400 > wpt.json
           kill `cat WPT.pid`
 
       - name: write commit

Makefile

@@ -47,7 +47,7 @@ help:
 
 # $(ZIG) commands
 # ------------
-.PHONY: build build-v8-snapshot build-dev run run-release shell test bench data end2end
+.PHONY: build build-v8-snapshot build-dev run run-release test bench data end2end
 
 ## Build v8 snapshot
 build-v8-snapshot:
@@ -77,11 +77,6 @@ run-debug: build-dev
 	@printf "\033[36mRunning...\033[0m\n"
 	@./zig-out/bin/lightpanda || (printf "\033[33mRun ERROR\033[0m\n"; exit 1;)
 
-## Run a JS shell in debug mode
-shell:
-	@printf "\033[36mBuilding shell...\033[0m\n"
-	@$(ZIG) build shell || (printf "\033[33mBuild ERROR\033[0m\n"; exit 1;)
-
 ## Test - `grep` is used to filter out the huge compile command on build
 ifeq ($(OS), macos)
 test:
@@ -106,4 +101,3 @@ install: build
 
 data:
 	cd src/data && go run public_suffix_list_gen.go > public_suffix_list.zig
-

src/SemanticTree.zig

@@ -38,6 +38,7 @@ page: *Page,
 arena: std.mem.Allocator,
 prune: bool = true,
 interactive_only: bool = false,
+max_depth: u32 = std.math.maxInt(u32) - 1,
 
 pub fn jsonStringify(self: @This(), jw: *std.json.Stringify) error{WriteFailed}!void {
     var visitor = JsonVisitor{ .jw = jw, .tree = self };
@@ -46,7 +47,7 @@ pub fn jsonStringify(self: @This(), jw: *std.json.Stringify) error{WriteFailed}!
         log.err(.app, "listener map failed", .{ .err = err });
         return error.WriteFailed;
     };
-    self.walk(self.dom_node, &xpath_buffer, null, &visitor, 1, listener_targets) catch |err| {
+    self.walk(self.dom_node, &xpath_buffer, null, &visitor, 1, listener_targets, 0) catch |err| {
         log.err(.app, "semantic tree json dump failed", .{ .err = err });
         return error.WriteFailed;
     };
@@ -59,7 +60,7 @@ pub fn textStringify(self: @This(), writer: *std.Io.Writer) error{WriteFailed}!v
         log.err(.app, "listener map failed", .{ .err = err });
         return error.WriteFailed;
     };
-    self.walk(self.dom_node, &xpath_buffer, null, &visitor, 1, listener_targets) catch |err| {
+    self.walk(self.dom_node, &xpath_buffer, null, &visitor, 1, listener_targets, 0) catch |err| {
         log.err(.app, "semantic tree text dump failed", .{ .err = err });
         return error.WriteFailed;
     };
@@ -72,7 +73,7 @@ const OptionData = struct {
 };
 
 const NodeData = struct {
-    id: u32,
+    id: CDPNode.Id,
     axn: AXNode,
     role: []const u8,
     name: ?[]const u8,
@@ -83,7 +84,9 @@ const NodeData = struct {
     node_name: []const u8,
 };
 
-fn walk(self: @This(), node: *Node, xpath_buffer: *std.ArrayList(u8), parent_name: ?[]const u8, visitor: anytype, index: usize, listener_targets: interactive.ListenerTargetMap) !void {
+fn walk(self: @This(), node: *Node, xpath_buffer: *std.ArrayList(u8), parent_name: ?[]const u8, visitor: anytype, index: usize, listener_targets: interactive.ListenerTargetMap, current_depth: u32) !void {
+    if (current_depth > self.max_depth) return;
+
     // 1. Skip non-content nodes
     if (node.is(Element)) |el| {
         const tag = el.getTag();
@@ -230,7 +233,7 @@ fn walk(self: @This(), node: *Node, xpath_buffer: *std.ArrayList(u8), parent_nam
             }
             gop.value_ptr.* += 1;
 
-            try self.walk(child, xpath_buffer, name, visitor, gop.value_ptr.*, listener_targets);
+            try self.walk(child, xpath_buffer, name, visitor, gop.value_ptr.*, listener_targets, current_depth + 1);
         }
     }
 
@@ -474,3 +477,56 @@ const TextVisitor = struct {
         }
     }
 };
+
+const testing = @import("testing.zig");
+
+test "SemanticTree backendDOMNodeId" {
+    var registry: CDPNode.Registry = .init(testing.allocator);
+    defer registry.deinit();
+
+    var page = try testing.pageTest("cdp/registry1.html");
+    defer testing.reset();
+    defer page._session.removePage();
+
+    const st: Self = .{
+        .dom_node = page.window._document.asNode(),
+        .registry = &registry,
+        .page = page,
+        .arena = testing.arena_allocator,
+        .prune = false,
+        .interactive_only = false,
+        .max_depth = std.math.maxInt(u32) - 1,
+    };
+
+    const json_str = try std.json.Stringify.valueAlloc(testing.allocator, st, .{});
+    defer testing.allocator.free(json_str);
+
+    try testing.expect(std.mem.indexOf(u8, json_str, "\"backendDOMNodeId\":") != null);
+}
+
+test "SemanticTree max_depth" {
+    var registry: CDPNode.Registry = .init(testing.allocator);
+    defer registry.deinit();
+
+    var page = try testing.pageTest("cdp/registry1.html");
+    defer testing.reset();
+    defer page._session.removePage();
+
+    const st: Self = .{
+        .dom_node = page.window._document.asNode(),
+        .registry = &registry,
+        .page = page,
+        .arena = testing.arena_allocator,
+        .prune = false,
+        .interactive_only = false,
+        .max_depth = 1,
+    };
+
+    var aw: std.Io.Writer.Allocating = .init(testing.allocator);
+    defer aw.deinit();
+
+    try st.textStringify(&aw.writer);
+    const text_str = aw.written();
+
+    try testing.expect(std.mem.indexOf(u8, text_str, "other") == null);
+}

src/browser/js/Local.zig

@@ -1212,6 +1212,12 @@ pub fn rejectPromise(self: *const Local, value: anytype) !js.Promise {
     return resolver.promise();
 }
 
+pub fn rejectErrorPromise(self: *const Local, value: js.PromiseResolver.RejectError) !js.Promise {
+    var resolver = js.PromiseResolver.init(self);
+    resolver.rejectError("Local.rejectPromise", value);
+    return resolver.promise();
+}
+
 pub fn resolvePromise(self: *const Local, value: anytype) !js.Promise {
     var resolver = js.PromiseResolver.init(self);
     resolver.resolve("Local.resolvePromise", value);

src/browser/js/PromiseResolver.zig

@@ -18,7 +18,9 @@
 
 const js = @import("js.zig");
 const v8 = js.v8;
+
 const log = @import("../../log.zig");
+const DOMException = @import("../webapi/DOMException.zig");
 
 const PromiseResolver = @This();
 
@@ -63,14 +65,19 @@ pub fn reject(self: PromiseResolver, comptime source: []const u8, value: anytype
     };
 }
 
-const RejectError = union(enum) {
+pub const RejectError = union(enum) {
     generic: []const u8,
     type_error: []const u8,
+    dom_exception: anyerror,
 };
 pub fn rejectError(self: PromiseResolver, comptime source: []const u8, err: RejectError) void {
     const handle = switch (err) {
         .type_error => |str| self.local.isolate.createTypeError(str),
         .generic => |str| self.local.isolate.createError(str),
+        .dom_exception => |exception| {
+            self.reject(source, DOMException.fromError(exception));
+            return;
+        },
     };
     self._reject(js.Value{ .handle = handle, .local = self.local }) catch |reject_err| {
         log.err(.bug, "rejectError", .{ .source = source, .err = reject_err, .persistent = false });

src/browser/js/bridge.zig

@@ -725,6 +725,8 @@ pub const JsApis = flattenTypes(&.{
     @import("../webapi/collections.zig"),
     @import("../webapi/Console.zig"),
     @import("../webapi/Crypto.zig"),
+    @import("../webapi/Permissions.zig"),
+    @import("../webapi/StorageManager.zig"),
     @import("../webapi/CSS.zig"),
     @import("../webapi/css/CSSRule.zig"),
     @import("../webapi/css/CSSRuleList.zig"),

src/browser/markdown.zig

@@ -124,352 +124,362 @@ fn hasVisibleContent(root: *Node) bool {
     return false;
 }
 
-fn ensureNewline(state: *State, writer: *std.Io.Writer) !void {
+const Context = struct {
-    if (!state.last_char_was_newline) {
+    state: State,
-        try writer.writeByte('\n');
+    writer: *std.Io.Writer,
-        state.last_char_was_newline = true;
+    page: *Page,
+
+    fn ensureNewline(self: *Context) !void {
+        if (!self.state.last_char_was_newline) {
+            try self.writer.writeByte('\n');
+            self.state.last_char_was_newline = true;
+        }
     }
-}
+
+    fn render(self: *Context, node: *Node) error{WriteFailed}!void {
+        switch (node._type) {
+            .document, .document_fragment => {
+                try self.renderChildren(node);
+            },
+            .element => |el| {
+                try self.renderElement(el);
+            },
+            .cdata => |cd| {
+                if (node.is(Node.CData.Text)) |_| {
+                    var text = cd.getData().str();
+                    if (self.state.pre_node) |pre| {
+                        if (node.parentNode() == pre and node.nextSibling() == null) {
+                            text = std.mem.trimRight(u8, text, " \t\r\n");
+                        }
+                    }
+                    try self.renderText(text);
+                }
+            },
+            else => {},
+        }
+    }
+
+    fn renderChildren(self: *Context, parent: *Node) !void {
+        var it = parent.childrenIterator();
+        while (it.next()) |child| {
+            try self.render(child);
+        }
+    }
+
+    fn renderElement(self: *Context, el: *Element) !void {
+        const tag = el.getTag();
+
+        if (!isVisibleElement(el)) return;
+
+        // --- Opening Tag Logic ---
+
+        // Ensure block elements start on a new line (double newline for paragraphs etc)
+        if (tag.isBlock() and !self.state.in_table) {
+            try self.ensureNewline();
+            if (shouldAddSpacing(tag)) {
+                try self.writer.writeByte('\n');
+            }
+        } else if (tag == .li or tag == .tr) {
+            try self.ensureNewline();
+        }
+
+        // Prefixes
+        switch (tag) {
+            .h1 => try self.writer.writeAll("# "),
+            .h2 => try self.writer.writeAll("## "),
+            .h3 => try self.writer.writeAll("### "),
+            .h4 => try self.writer.writeAll("#### "),
+            .h5 => try self.writer.writeAll("##### "),
+            .h6 => try self.writer.writeAll("###### "),
+            .ul => {
+                if (self.state.list_depth < self.state.list_stack.len) {
+                    self.state.list_stack[self.state.list_depth] = .{ .type = .unordered, .index = 0 };
+                    self.state.list_depth += 1;
+                }
+            },
+            .ol => {
+                if (self.state.list_depth < self.state.list_stack.len) {
+                    self.state.list_stack[self.state.list_depth] = .{ .type = .ordered, .index = 1 };
+                    self.state.list_depth += 1;
+                }
+            },
+            .li => {
+                const indent = if (self.state.list_depth > 0) self.state.list_depth - 1 else 0;
+                for (0..indent) |_| try self.writer.writeAll("  ");
+
+                if (self.state.list_depth > 0 and self.state.list_stack[self.state.list_depth - 1].type == .ordered) {
+                    const current_list = &self.state.list_stack[self.state.list_depth - 1];
+                    try self.writer.print("{d}. ", .{current_list.index});
+                    current_list.index += 1;
+                } else {
+                    try self.writer.writeAll("- ");
+                }
+                self.state.last_char_was_newline = false;
+            },
+            .table => {
+                self.state.in_table = true;
+                self.state.table_row_index = 0;
+                self.state.table_col_count = 0;
+            },
+            .tr => {
+                self.state.table_col_count = 0;
+                try self.writer.writeByte('|');
+            },
+            .td, .th => {
+                // Note: leading pipe handled by previous cell closing or tr opening
+                self.state.last_char_was_newline = false;
+                try self.writer.writeByte(' ');
+            },
+            .blockquote => {
+                try self.writer.writeAll("> ");
+                self.state.last_char_was_newline = false;
+            },
+            .pre => {
+                try self.writer.writeAll("```\n");
+                self.state.pre_node = el.asNode();
+                self.state.last_char_was_newline = true;
+            },
+            .code => {
+                if (self.state.pre_node == null) {
+                    try self.writer.writeByte('`');
+                    self.state.in_code = true;
+                    self.state.last_char_was_newline = false;
+                }
+            },
+            .b, .strong => {
+                try self.writer.writeAll("**");
+                self.state.last_char_was_newline = false;
+            },
+            .i, .em => {
+                try self.writer.writeAll("*");
+                self.state.last_char_was_newline = false;
+            },
+            .s, .del => {
+                try self.writer.writeAll("~~");
+                self.state.last_char_was_newline = false;
+            },
+            .hr => {
+                try self.writer.writeAll("---\n");
+                self.state.last_char_was_newline = true;
+                return;
+            },
+            .br => {
+                if (self.state.in_table) {
+                    try self.writer.writeByte(' ');
+                } else {
+                    try self.writer.writeByte('\n');
+                    self.state.last_char_was_newline = true;
+                }
+                return;
+            },
+            .img => {
+                try self.writer.writeAll("![");
+                if (el.getAttributeSafe(comptime .wrap("alt"))) |alt| {
+                    try self.escape(alt);
+                }
+                try self.writer.writeAll("](");
+                if (el.getAttributeSafe(comptime .wrap("src"))) |src| {
+                    const absolute_src = URL.resolve(self.page.call_arena, self.page.base(), src, .{ .encode = true }) catch src;
+                    try self.writer.writeAll(absolute_src);
+                }
+                try self.writer.writeAll(")");
+                self.state.last_char_was_newline = false;
+                return;
+            },
+            .anchor => {
+                const has_content = hasVisibleContent(el.asNode());
+                const label = getAnchorLabel(el);
+                const href_raw = el.getAttributeSafe(comptime .wrap("href"));
+
+                if (!has_content and label == null and href_raw == null) return;
+
+                const has_block = hasBlockDescendant(el.asNode());
+                const href = if (href_raw) |h| URL.resolve(self.page.call_arena, self.page.base(), h, .{ .encode = true }) catch h else null;
+
+                if (has_block) {
+                    try self.renderChildren(el.asNode());
+                    if (href) |h| {
+                        if (!self.state.last_char_was_newline) try self.writer.writeByte('\n');
+                        try self.writer.writeAll("([](");
+                        try self.writer.writeAll(h);
+                        try self.writer.writeAll("))\n");
+                        self.state.last_char_was_newline = true;
+                    }
+                    return;
+                }
+
+                if (isStandaloneAnchor(el)) {
+                    if (!self.state.last_char_was_newline) try self.writer.writeByte('\n');
+                    try self.writer.writeByte('[');
+                    if (has_content) {
+                        try self.renderChildren(el.asNode());
+                    } else {
+                        try self.writer.writeAll(label orelse "");
+                    }
+                    try self.writer.writeAll("](");
+                    if (href) |h| {
+                        try self.writer.writeAll(h);
+                    }
+                    try self.writer.writeAll(")\n");
+                    self.state.last_char_was_newline = true;
+                    return;
+                }
+
+                try self.writer.writeByte('[');
+                if (has_content) {
+                    try self.renderChildren(el.asNode());
+                } else {
+                    try self.writer.writeAll(label orelse "");
+                }
+                try self.writer.writeAll("](");
+                if (href) |h| {
+                    try self.writer.writeAll(h);
+                }
+                try self.writer.writeByte(')');
+                self.state.last_char_was_newline = false;
+                return;
+            },
+            .input => {
+                const type_attr = el.getAttributeSafe(comptime .wrap("type")) orelse return;
+                if (std.ascii.eqlIgnoreCase(type_attr, "checkbox")) {
+                    const checked = el.getAttributeSafe(comptime .wrap("checked")) != null;
+                    try self.writer.writeAll(if (checked) "[x] " else "[ ] ");
+                    self.state.last_char_was_newline = false;
+                }
+                return;
+            },
+            else => {},
+        }
+
+        // --- Render Children ---
+        try self.renderChildren(el.asNode());
+
+        // --- Closing Tag Logic ---
+
+        // Suffixes
+        switch (tag) {
+            .pre => {
+                if (!self.state.last_char_was_newline) {
+                    try self.writer.writeByte('\n');
+                }
+                try self.writer.writeAll("```\n");
+                self.state.pre_node = null;
+                self.state.last_char_was_newline = true;
+            },
+            .code => {
+                if (self.state.pre_node == null) {
+                    try self.writer.writeByte('`');
+                    self.state.in_code = false;
+                    self.state.last_char_was_newline = false;
+                }
+            },
+            .b, .strong => {
+                try self.writer.writeAll("**");
+                self.state.last_char_was_newline = false;
+            },
+            .i, .em => {
+                try self.writer.writeAll("*");
+                self.state.last_char_was_newline = false;
+            },
+            .s, .del => {
+                try self.writer.writeAll("~~");
+                self.state.last_char_was_newline = false;
+            },
+            .blockquote => {},
+            .ul, .ol => {
+                if (self.state.list_depth > 0) self.state.list_depth -= 1;
+            },
+            .table => {
+                self.state.in_table = false;
+            },
+            .tr => {
+                try self.writer.writeByte('\n');
+                if (self.state.table_row_index == 0) {
+                    try self.writer.writeByte('|');
+                    for (0..self.state.table_col_count) |_| {
+                        try self.writer.writeAll("---|");
+                    }
+                    try self.writer.writeByte('\n');
+                }
+                self.state.table_row_index += 1;
+                self.state.last_char_was_newline = true;
+            },
+            .td, .th => {
+                try self.writer.writeAll(" |");
+                self.state.table_col_count += 1;
+                self.state.last_char_was_newline = false;
+            },
+            else => {},
+        }
+
+        // Post-block newlines
+        if (tag.isBlock() and !self.state.in_table) {
+            try self.ensureNewline();
+        }
+    }
+
+    fn renderText(self: *Context, text: []const u8) !void {
+        if (text.len == 0) return;
+
+        if (self.state.pre_node) |_| {
+            try self.writer.writeAll(text);
+            self.state.last_char_was_newline = text[text.len - 1] == '\n';
+            return;
+        }
+
+        // Check for pure whitespace
+        if (isAllWhitespace(text)) {
+            if (!self.state.last_char_was_newline) {
+                try self.writer.writeByte(' ');
+            }
+            return;
+        }
+
+        // Collapse whitespace
+        var it = std.mem.tokenizeAny(u8, text, " \t\n\r");
+        var first = true;
+        while (it.next()) |word| {
+            if (!first or (!self.state.last_char_was_newline and std.ascii.isWhitespace(text[0]))) {
+                try self.writer.writeByte(' ');
+            }
+
+            try self.escape(word);
+            self.state.last_char_was_newline = false;
+            first = false;
+        }
+
+        // Handle trailing whitespace from the original text
+        if (!first and !self.state.last_char_was_newline and std.ascii.isWhitespace(text[text.len - 1])) {
+            try self.writer.writeByte(' ');
+        }
+    }
+
+    fn escape(self: *Context, text: []const u8) !void {
+        for (text) |c| {
+            switch (c) {
+                '\\', '`', '*', '_', '{', '}', '[', ']', '(', ')', '#', '+', '-', '!', '|' => {
+                    try self.writer.writeByte('\\');
+                    try self.writer.writeByte(c);
+                },
+                else => try self.writer.writeByte(c),
+            }
+        }
+    }
+};
 
 pub fn dump(node: *Node, opts: Opts, writer: *std.Io.Writer, page: *Page) !void {
     _ = opts;
-    var state = State{};
+    var ctx: Context = .{
-    try render(node, &state, writer, page);
+        .state = .{},
-    if (!state.last_char_was_newline) {
+        .writer = writer,
+        .page = page,
+    };
+    try ctx.render(node);
+    if (!ctx.state.last_char_was_newline) {
         try writer.writeByte('\n');
     }
 }
 
-fn render(node: *Node, state: *State, writer: *std.Io.Writer, page: *Page) error{WriteFailed}!void {
-    switch (node._type) {
-        .document, .document_fragment => {
-            try renderChildren(node, state, writer, page);
-        },
-        .element => |el| {
-            try renderElement(el, state, writer, page);
-        },
-        .cdata => |cd| {
-            if (node.is(Node.CData.Text)) |_| {
-                var text = cd.getData().str();
-                if (state.pre_node) |pre| {
-                    if (node.parentNode() == pre and node.nextSibling() == null) {
-                        text = std.mem.trimRight(u8, text, " \t\r\n");
-                    }
-                }
-                try renderText(text, state, writer);
-            }
-        },
-        else => {},
-    }
-}
-
-fn renderChildren(parent: *Node, state: *State, writer: *std.Io.Writer, page: *Page) !void {
-    var it = parent.childrenIterator();
-    while (it.next()) |child| {
-        try render(child, state, writer, page);
-    }
-}
-
-fn renderElement(el: *Element, state: *State, writer: *std.Io.Writer, page: *Page) !void {
-    const tag = el.getTag();
-
-    if (!isVisibleElement(el)) return;
-
-    // --- Opening Tag Logic ---
-
-    // Ensure block elements start on a new line (double newline for paragraphs etc)
-    if (tag.isBlock() and !state.in_table) {
-        try ensureNewline(state, writer);
-        if (shouldAddSpacing(tag)) {
-            try writer.writeByte('\n');
-        }
-    } else if (tag == .li or tag == .tr) {
-        try ensureNewline(state, writer);
-    }
-
-    // Prefixes
-    switch (tag) {
-        .h1 => try writer.writeAll("# "),
-        .h2 => try writer.writeAll("## "),
-        .h3 => try writer.writeAll("### "),
-        .h4 => try writer.writeAll("#### "),
-        .h5 => try writer.writeAll("##### "),
-        .h6 => try writer.writeAll("###### "),
-        .ul => {
-            if (state.list_depth < state.list_stack.len) {
-                state.list_stack[state.list_depth] = .{ .type = .unordered, .index = 0 };
-                state.list_depth += 1;
-            }
-        },
-        .ol => {
-            if (state.list_depth < state.list_stack.len) {
-                state.list_stack[state.list_depth] = .{ .type = .ordered, .index = 1 };
-                state.list_depth += 1;
-            }
-        },
-        .li => {
-            const indent = if (state.list_depth > 0) state.list_depth - 1 else 0;
-            for (0..indent) |_| try writer.writeAll("  ");
-
-            if (state.list_depth > 0 and state.list_stack[state.list_depth - 1].type == .ordered) {
-                const current_list = &state.list_stack[state.list_depth - 1];
-                try writer.print("{d}. ", .{current_list.index});
-                current_list.index += 1;
-            } else {
-                try writer.writeAll("- ");
-            }
-            state.last_char_was_newline = false;
-        },
-        .table => {
-            state.in_table = true;
-            state.table_row_index = 0;
-            state.table_col_count = 0;
-        },
-        .tr => {
-            state.table_col_count = 0;
-            try writer.writeByte('|');
-        },
-        .td, .th => {
-            // Note: leading pipe handled by previous cell closing or tr opening
-            state.last_char_was_newline = false;
-            try writer.writeByte(' ');
-        },
-        .blockquote => {
-            try writer.writeAll("> ");
-            state.last_char_was_newline = false;
-        },
-        .pre => {
-            try writer.writeAll("```\n");
-            state.pre_node = el.asNode();
-            state.last_char_was_newline = true;
-        },
-        .code => {
-            if (state.pre_node == null) {
-                try writer.writeByte('`');
-                state.in_code = true;
-                state.last_char_was_newline = false;
-            }
-        },
-        .b, .strong => {
-            try writer.writeAll("**");
-            state.last_char_was_newline = false;
-        },
-        .i, .em => {
-            try writer.writeAll("*");
-            state.last_char_was_newline = false;
-        },
-        .s, .del => {
-            try writer.writeAll("~~");
-            state.last_char_was_newline = false;
-        },
-        .hr => {
-            try writer.writeAll("---\n");
-            state.last_char_was_newline = true;
-            return;
-        },
-        .br => {
-            if (state.in_table) {
-                try writer.writeByte(' ');
-            } else {
-                try writer.writeByte('\n');
-                state.last_char_was_newline = true;
-            }
-            return;
-        },
-        .img => {
-            try writer.writeAll("![");
-            if (el.getAttributeSafe(comptime .wrap("alt"))) |alt| {
-                try escapeMarkdown(writer, alt);
-            }
-            try writer.writeAll("](");
-            if (el.getAttributeSafe(comptime .wrap("src"))) |src| {
-                const absolute_src = URL.resolve(page.call_arena, page.base(), src, .{ .encode = true }) catch src;
-                try writer.writeAll(absolute_src);
-            }
-            try writer.writeAll(")");
-            state.last_char_was_newline = false;
-            return;
-        },
-        .anchor => {
-            const has_content = hasVisibleContent(el.asNode());
-            const label = getAnchorLabel(el);
-            const href_raw = el.getAttributeSafe(comptime .wrap("href"));
-
-            if (!has_content and label == null and href_raw == null) return;
-
-            const has_block = hasBlockDescendant(el.asNode());
-            const href = if (href_raw) |h| URL.resolve(page.call_arena, page.base(), h, .{ .encode = true }) catch h else null;
-
-            if (has_block) {
-                try renderChildren(el.asNode(), state, writer, page);
-                if (href) |h| {
-                    if (!state.last_char_was_newline) try writer.writeByte('\n');
-                    try writer.writeAll("([](");
-                    try writer.writeAll(h);
-                    try writer.writeAll("))\n");
-                    state.last_char_was_newline = true;
-                }
-                return;
-            }
-
-            if (isStandaloneAnchor(el)) {
-                if (!state.last_char_was_newline) try writer.writeByte('\n');
-                try writer.writeByte('[');
-                if (has_content) {
-                    try renderChildren(el.asNode(), state, writer, page);
-                } else {
-                    try writer.writeAll(label orelse "");
-                }
-                try writer.writeAll("](");
-                if (href) |h| {
-                    try writer.writeAll(h);
-                }
-                try writer.writeAll(")\n");
-                state.last_char_was_newline = true;
-                return;
-            }
-
-            try writer.writeByte('[');
-            if (has_content) {
-                try renderChildren(el.asNode(), state, writer, page);
-            } else {
-                try writer.writeAll(label orelse "");
-            }
-            try writer.writeAll("](");
-            if (href) |h| {
-                try writer.writeAll(h);
-            }
-            try writer.writeByte(')');
-            state.last_char_was_newline = false;
-            return;
-        },
-        .input => {
-            const type_attr = el.getAttributeSafe(comptime .wrap("type")) orelse return;
-            if (std.ascii.eqlIgnoreCase(type_attr, "checkbox")) {
-                const checked = el.getAttributeSafe(comptime .wrap("checked")) != null;
-                try writer.writeAll(if (checked) "[x] " else "[ ] ");
-                state.last_char_was_newline = false;
-            }
-            return;
-        },
-        else => {},
-    }
-
-    // --- Render Children ---
-    try renderChildren(el.asNode(), state, writer, page);
-
-    // --- Closing Tag Logic ---
-
-    // Suffixes
-    switch (tag) {
-        .pre => {
-            if (!state.last_char_was_newline) {
-                try writer.writeByte('\n');
-            }
-            try writer.writeAll("```\n");
-            state.pre_node = null;
-            state.last_char_was_newline = true;
-        },
-        .code => {
-            if (state.pre_node == null) {
-                try writer.writeByte('`');
-                state.in_code = false;
-                state.last_char_was_newline = false;
-            }
-        },
-        .b, .strong => {
-            try writer.writeAll("**");
-            state.last_char_was_newline = false;
-        },
-        .i, .em => {
-            try writer.writeAll("*");
-            state.last_char_was_newline = false;
-        },
-        .s, .del => {
-            try writer.writeAll("~~");
-            state.last_char_was_newline = false;
-        },
-        .blockquote => {},
-        .ul, .ol => {
-            if (state.list_depth > 0) state.list_depth -= 1;
-        },
-        .table => {
-            state.in_table = false;
-        },
-        .tr => {
-            try writer.writeByte('\n');
-            if (state.table_row_index == 0) {
-                try writer.writeByte('|');
-                for (0..state.table_col_count) |_| {
-                    try writer.writeAll("---|");
-                }
-                try writer.writeByte('\n');
-            }
-            state.table_row_index += 1;
-            state.last_char_was_newline = true;
-        },
-        .td, .th => {
-            try writer.writeAll(" |");
-            state.table_col_count += 1;
-            state.last_char_was_newline = false;
-        },
-        else => {},
-    }
-
-    // Post-block newlines
-    if (tag.isBlock() and !state.in_table) {
-        try ensureNewline(state, writer);
-    }
-}
-
-fn renderText(text: []const u8, state: *State, writer: *std.Io.Writer) !void {
-    if (text.len == 0) return;
-
-    if (state.pre_node) |_| {
-        try writer.writeAll(text);
-        state.last_char_was_newline = text[text.len - 1] == '\n';
-        return;
-    }
-
-    // Check for pure whitespace
-    if (isAllWhitespace(text)) {
-        if (!state.last_char_was_newline) {
-            try writer.writeByte(' ');
-        }
-        return;
-    }
-
-    // Collapse whitespace
-    var it = std.mem.tokenizeAny(u8, text, " \t\n\r");
-    var first = true;
-    while (it.next()) |word| {
-        if (!first or (!state.last_char_was_newline and std.ascii.isWhitespace(text[0]))) {
-            try writer.writeByte(' ');
-        }
-
-        try escapeMarkdown(writer, word);
-        state.last_char_was_newline = false;
-        first = false;
-    }
-
-    // Handle trailing whitespace from the original text
-    if (!first and !state.last_char_was_newline and std.ascii.isWhitespace(text[text.len - 1])) {
-        try writer.writeByte(' ');
-    }
-}
-
-fn escapeMarkdown(writer: *std.Io.Writer, text: []const u8) !void {
-    for (text) |c| {
-        switch (c) {
-            '\\', '`', '*', '_', '{', '}', '[', ']', '(', ')', '#', '+', '-', '!', '|' => {
-                try writer.writeByte('\\');
-                try writer.writeByte(c);
-            },
-            else => try writer.writeByte(c),
-        }
-    }
-}
-
 fn testMarkdownHTML(html: []const u8, expected: []const u8) !void {
     const testing = @import("../testing.zig");
     const page = try testing.test_session.createPage();

src/browser/tests/navigator/navigator.html

@@ -27,3 +27,44 @@
   testing.expectEqual(false, navigator.javaEnabled());
   testing.expectEqual(false, navigator.webdriver);
 </script>
+
+<script id=permission_query>
+    testing.async(async (restore) => {
+      const p = navigator.permissions.query({ name: 'notifications' });
+      testing.expectTrue(p instanceof Promise);
+      const status = await p;
+      restore();
+      testing.expectEqual('prompt', status.state);
+      testing.expectEqual('notifications', status.name);
+  });
+</script>
+
+<script id=storage_estimate>
+  testing.async(async (restore) => {
+    const p = navigator.storage.estimate();
+    testing.expectTrue(p instanceof Promise);
+
+    const estimate = await p;
+    restore();
+    testing.expectEqual(0, estimate.usage);
+    testing.expectEqual(1024 * 1024 * 1024, estimate.quota);
+  });
+</script>
+
+<script id=deviceMemory>
+  testing.expectEqual(8, navigator.deviceMemory);
+</script>
+
+<script id=getBattery>
+  testing.async(async (restore) => {
+    const p = navigator.getBattery();
+    try {
+      await p;
+      testing.fail('getBattery should reject');
+    } catch (err) {
+      restore();
+      testing.expectEqual('NotSupportedError', err.name);
+    }
+  });
+</script>
+

src/browser/tests/net/fetch.html

@@ -225,3 +225,17 @@
     URL.revokeObjectURL(blobUrl);
   });
 </script>
+
+<script id=abort>
+  testing.async(async (restore) => {
+    const controller = new AbortController();
+    controller.abort();
+    try {
+      await fetch('http://127.0.0.1:9582/xhr', { signal: controller.signal });
+      testain.fail('fetch should have been aborted');
+    } catch (e) {
+      restore();
+      testing.expectEqual("AbortError", e.name);
+    }
+  });
+</script>

src/browser/webapi/Navigator.zig

@@ -18,13 +18,21 @@
 
 const std = @import("std");
 const builtin = @import("builtin");
+
+const log = @import("../../log.zig");
+
 const js = @import("../js/js.zig");
 const Page = @import("../Page.zig");
+
 const PluginArray = @import("PluginArray.zig");
+const Permissions = @import("Permissions.zig");
+const StorageManager = @import("StorageManager.zig");
 
 const Navigator = @This();
 _pad: bool = false,
 _plugins: PluginArray = .{},
+_permissions: Permissions = .{},
+_storage: StorageManager = .{},
 
 pub const init: Navigator = .{};
 
@@ -55,6 +63,19 @@ pub fn getPlugins(self: *Navigator) *PluginArray {
     return &self._plugins;
 }
 
+pub fn getPermissions(self: *Navigator) *Permissions {
+    return &self._permissions;
+}
+
+pub fn getStorage(self: *Navigator) *StorageManager {
+    return &self._storage;
+}
+
+pub fn getBattery(_: *const Navigator, page: *Page) !js.Promise {
+    log.info(.not_implemented, "navigator.getBattery", .{});
+    return page.js.local.?.rejectErrorPromise(.{ .dom_exception = error.NotSupported });
+}
+
 pub fn registerProtocolHandler(_: *const Navigator, scheme: []const u8, url: [:0]const u8, page: *const Page) !void {
     try validateProtocolHandlerScheme(scheme);
     try validateProtocolHandlerURL(url, page);
@@ -144,6 +165,7 @@ pub const JsApi = struct {
     pub const onLine = bridge.property(true, .{ .template = false });
     pub const cookieEnabled = bridge.property(true, .{ .template = false });
     pub const hardwareConcurrency = bridge.property(4, .{ .template = false });
+    pub const deviceMemory = bridge.property(@as(f64, 8.0), .{ .template = false });
     pub const maxTouchPoints = bridge.property(0, .{ .template = false });
     pub const vendor = bridge.property("", .{ .template = false });
     pub const product = bridge.property("Gecko", .{ .template = false });
@@ -156,4 +178,12 @@ pub const JsApi = struct {
 
     // Methods
     pub const javaEnabled = bridge.function(Navigator.javaEnabled, .{});
+    pub const getBattery = bridge.function(Navigator.getBattery, .{});
+    pub const permissions = bridge.accessor(Navigator.getPermissions, null, .{});
+    pub const storage = bridge.accessor(Navigator.getStorage, null, .{});
 };
+
+const testing = @import("../../testing.zig");
+test "WebApi: Navigator" {
+    try testing.htmlRunner("navigator", .{});
+}

src/browser/webapi/Permissions.zig

@@ -0,0 +1,94 @@
+// Copyright (C) 2023-2025 Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const std = @import("std");
+const js = @import("../js/js.zig");
+const Page = @import("../Page.zig");
+const Session = @import("../Session.zig");
+
+const Allocator = std.mem.Allocator;
+
+pub fn registerTypes() []const type {
+    return &.{ Permissions, PermissionStatus };
+}
+
+const Permissions = @This();
+
+// Padding to avoid zero-size struct pointer collisions
+_pad: bool = false,
+
+const QueryDescriptor = struct {
+    name: []const u8,
+};
+// We always report 'prompt' (the default safe value — neither granted nor denied).
+pub fn query(_: *const Permissions, qd: QueryDescriptor, page: *Page) !js.Promise {
+    const arena = try page.getArena(.{ .debug = "PermissionStatus" });
+    errdefer page.releaseArena(arena);
+
+    const status = try arena.create(PermissionStatus);
+    status.* = .{
+        ._arena = arena,
+        ._state = "prompt",
+        ._name = try arena.dupe(u8, qd.name),
+    };
+    return page.js.local.?.resolvePromise(status);
+}
+
+const PermissionStatus = struct {
+    _arena: Allocator,
+    _name: []const u8,
+    _state: []const u8,
+
+    pub fn deinit(self: *PermissionStatus, _: bool, session: *Session) void {
+        session.releaseArena(self._arena);
+    }
+
+    fn getName(self: *const PermissionStatus) []const u8 {
+        return self._name;
+    }
+
+    fn getState(self: *const PermissionStatus) []const u8 {
+        return self._state;
+    }
+
+    pub const JsApi = struct {
+        pub const bridge = js.Bridge(PermissionStatus);
+        pub const Meta = struct {
+            pub const name = "PermissionStatus";
+            pub const prototype_chain = bridge.prototypeChain();
+            pub var class_id: bridge.ClassId = undefined;
+            pub const weak = true;
+            pub const finalizer = bridge.finalizer(PermissionStatus.deinit);
+        };
+        pub const name = bridge.accessor(getName, null, .{});
+        pub const state = bridge.accessor(getState, null, .{});
+    };
+};
+
+pub const JsApi = struct {
+    pub const bridge = js.Bridge(Permissions);
+
+    pub const Meta = struct {
+        pub const name = "Permissions";
+        pub const prototype_chain = bridge.prototypeChain();
+        pub var class_id: bridge.ClassId = undefined;
+        pub const empty_with_no_proto = true;
+    };
+
+    pub const query = bridge.function(Permissions.query, .{ .dom_exception = true });
+};

src/browser/webapi/StorageManager.zig

@@ -0,0 +1,71 @@
+// Copyright (C) 2023-2026 Lightpanda (Selecy SAS)
+//
+// Francis Bouvier <francis@lightpanda.io>
+// Pierre Tachoire <pierre@lightpanda.io>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as
+// published by the Free Software Foundation, either version 3 of the
+// License, or (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+const js = @import("../js/js.zig");
+const Page = @import("../Page.zig");
+
+pub fn registerTypes() []const type {
+    return &.{ StorageManager, StorageEstimate };
+}
+
+const StorageManager = @This();
+
+_pad: bool = false,
+
+pub fn estimate(_: *const StorageManager, page: *Page) !js.Promise {
+    const est = try page._factory.create(StorageEstimate{
+        ._usage = 0,
+        ._quota = 1024 * 1024 * 1024, // 1 GiB
+    });
+    return page.js.local.?.resolvePromise(est);
+}
+
+const StorageEstimate = struct {
+    _quota: u64,
+    _usage: u64,
+
+    fn getUsage(self: *const StorageEstimate) u64 {
+        return self._usage;
+    }
+
+    fn getQuota(self: *const StorageEstimate) u64 {
+        return self._quota;
+    }
+
+    pub const JsApi = struct {
+        pub const bridge = js.Bridge(StorageEstimate);
+        pub const Meta = struct {
+            pub const name = "StorageEstimate";
+            pub const prototype_chain = bridge.prototypeChain();
+            pub var class_id: bridge.ClassId = undefined;
+        };
+        pub const quota = bridge.accessor(getQuota, null, .{});
+        pub const usage = bridge.accessor(getUsage, null, .{});
+    };
+};
+
+pub const JsApi = struct {
+    pub const bridge = js.Bridge(StorageManager);
+    pub const Meta = struct {
+        pub const name = "StorageManager";
+        pub const prototype_chain = bridge.prototypeChain();
+        pub var class_id: bridge.ClassId = undefined;
+        pub const empty_with_no_proto = true;
+    };
+    pub const estimate = bridge.function(StorageManager.estimate, .{});
+};

src/browser/webapi/net/Fetch.zig

@@ -28,6 +28,8 @@ const URL = @import("../../URL.zig");
 const Blob = @import("../Blob.zig");
 const Request = @import("Request.zig");
 const Response = @import("Response.zig");
+const AbortSignal = @import("../AbortSignal.zig");
+const DOMException = @import("../DOMException.zig");
 
 const IS_DEBUG = @import("builtin").mode == .Debug;
 
@@ -39,6 +41,7 @@ _buf: std.ArrayList(u8),
 _response: *Response,
 _resolver: js.PromiseResolver.Global,
 _owns_response: bool,
+_signal: ?*AbortSignal,
 
 pub const Input = Request.Input;
 pub const InitOpts = Request.InitOpts;
@@ -47,6 +50,13 @@ pub fn init(input: Input, options: ?InitOpts, page: *Page) !js.Promise {
     const request = try Request.init(input, options, page);
     const resolver = page.js.local.?.createPromiseResolver();
 
+    if (request._signal) |signal| {
+        if (signal._aborted) {
+            resolver.reject("fetch aborted", DOMException.init("The operation was aborted.", "AbortError"));
+            return resolver.promise();
+        }
+    }
+
     if (std.mem.startsWith(u8, request._url, "blob:")) {
         return handleBlobUrl(request._url, resolver, page);
     }
@@ -62,6 +72,7 @@ pub fn init(input: Input, options: ?InitOpts, page: *Page) !js.Promise {
         ._resolver = try resolver.persist(),
         ._response = response,
         ._owns_response = true,
+        ._signal = request._signal,
     };
 
     const http_client = page._session.browser.http_client;
@@ -126,6 +137,12 @@ fn httpStartCallback(transfer: *HttpClient.Transfer) !void {
 fn httpHeaderDoneCallback(transfer: *HttpClient.Transfer) !bool {
     const self: *Fetch = @ptrCast(@alignCast(transfer.ctx));
 
+    if (self._signal) |signal| {
+        if (signal._aborted) {
+            return false;
+        }
+    }
+
     const arena = self._response._arena;
     if (transfer.getContentLength()) |cl| {
         try self._buf.ensureTotalCapacity(arena, cl);
@@ -175,6 +192,14 @@ fn httpHeaderDoneCallback(transfer: *HttpClient.Transfer) !bool {
 
 fn httpDataCallback(transfer: *HttpClient.Transfer, data: []const u8) !void {
     const self: *Fetch = @ptrCast(@alignCast(transfer.ctx));
+
+    // Check if aborted
+    if (self._signal) |signal| {
+        if (signal._aborted) {
+            return error.Abort;
+        }
+    }
+
     try self._buf.appendSlice(self._response._arena, data);
 }
 

src/browser/webapi/net/Request.zig

@@ -25,6 +25,7 @@ const URL = @import("../URL.zig");
 const Page = @import("../../Page.zig");
 const Headers = @import("Headers.zig");
 const Blob = @import("../Blob.zig");
+const AbortSignal = @import("../AbortSignal.zig");
 const Allocator = std.mem.Allocator;
 
 const Request = @This();
@@ -36,6 +37,7 @@ _body: ?[]const u8,
 _arena: Allocator,
 _cache: Cache,
 _credentials: Credentials,
+_signal: ?*AbortSignal,
 
 pub const Input = union(enum) {
     request: *Request,
@@ -48,6 +50,7 @@ pub const InitOpts = struct {
     body: ?[]const u8 = null,
     cache: Cache = .default,
     credentials: Credentials = .@"same-origin",
+    signal: ?*AbortSignal = null,
 };
 
 const Credentials = enum {
@@ -97,6 +100,13 @@ pub fn init(input: Input, opts_: ?InitOpts, page: *Page) !*Request {
         .request => |r| r._body,
     };
 
+    const signal = if (opts.signal) |s|
+        s
+    else switch (input) {
+        .url => null,
+        .request => |r| r._signal,
+    };
+
     return page._factory.create(Request{
         ._url = url,
         ._arena = arena,
@@ -105,6 +115,7 @@ pub fn init(input: Input, opts_: ?InitOpts, page: *Page) !*Request {
         ._cache = opts.cache,
         ._credentials = opts.credentials,
         ._body = body,
+        ._signal = signal,
     });
 }
 
@@ -144,6 +155,10 @@ pub fn getCredentials(self: *const Request) []const u8 {
     return @tagName(self._credentials);
 }
 
+pub fn getSignal(self: *const Request) ?*AbortSignal {
+    return self._signal;
+}
+
 pub fn getHeaders(self: *Request, page: *Page) !*Headers {
     if (self._headers) |headers| {
         return headers;
@@ -200,6 +215,7 @@ pub fn clone(self: *const Request, page: *Page) !*Request {
         ._cache = self._cache,
         ._credentials = self._credentials,
         ._body = self._body,
+        ._signal = self._signal,
     });
 }
 
@@ -218,6 +234,7 @@ pub const JsApi = struct {
     pub const headers = bridge.accessor(Request.getHeaders, null, .{});
     pub const cache = bridge.accessor(Request.getCache, null, .{});
     pub const credentials = bridge.accessor(Request.getCredentials, null, .{});
+    pub const signal = bridge.accessor(Request.getSignal, null, .{});
     pub const blob = bridge.function(Request.blob, .{});
     pub const text = bridge.function(Request.text, .{});
     pub const json = bridge.function(Request.json, .{});

src/cdp/domains/lp.zig

@@ -53,12 +53,18 @@ fn getSemanticTree(cmd: anytype) !void {
         format: ?enum { text } = null,
         prune: ?bool = null,
         interactiveOnly: ?bool = null,
+        backendNodeId: ?Node.Id = null,
+        maxDepth: ?u32 = null,
     };
     const params = (try cmd.params(Params)) orelse Params{};
 
     const bc = cmd.browser_context orelse return error.NoBrowserContext;
     const page = bc.session.currentPage() orelse return error.PageNotLoaded;
-    const dom_node = page.document.asNode();
+
+    const dom_node = if (params.backendNodeId) |nodeId|
+        (bc.node_registry.lookup_by_id.get(nodeId) orelse return error.InvalidNodeId).dom
+    else
+        page.document.asNode();
 
     var st = SemanticTree{
         .dom_node = dom_node,
@@ -67,6 +73,7 @@ fn getSemanticTree(cmd: anytype) !void {
         .arena = cmd.arena,
         .prune = params.prune orelse true,
         .interactive_only = params.interactiveOnly orelse false,
+        .max_depth = params.maxDepth orelse std.math.maxInt(u32) - 1,
     };
 
     if (params.format) |format| {

src/mcp/tools.zig

@@ -70,7 +70,9 @@ pub const tool_list = [_]protocol.Tool{
             \\{
             \\  "type": "object",
             \\  "properties": {
-            \\    "url": { "type": "string", "description": "Optional URL to navigate to before fetching the semantic tree." }
+            \\    "url": { "type": "string", "description": "Optional URL to navigate to before fetching the semantic tree." },
+            \\    "backendNodeId": { "type": "integer", "description": "Optional backend node ID to get the tree for a specific element instead of the document root." },
+            \\    "maxDepth": { "type": "integer", "description": "Optional maximum depth of the tree to return. Useful for exploring high-level structure first." }
             \\  }
             \\}
         ),
@@ -161,6 +163,8 @@ const ToolStreamingText = struct {
     action: enum { markdown, links, semantic_tree },
     registry: ?*CDPNode.Registry = null,
     arena: ?std.mem.Allocator = null,
+    backendNodeId: ?u32 = null,
+    maxDepth: ?u32 = null,
 
     pub fn jsonStringify(self: @This(), jw: *std.json.Stringify) !void {
         try jw.beginWriteRaw();
@@ -196,12 +200,24 @@ const ToolStreamingText = struct {
                 }
             },
             .semantic_tree => {
+                var root_node = self.page.document.asNode();
+                if (self.backendNodeId) |node_id| {
+                    if (self.registry) |registry| {
+                        if (registry.lookup_by_id.get(node_id)) |n| {
+                            root_node = n.dom;
+                        } else {
+                            log.warn(.mcp, "semantic_tree id missing", .{ .id = node_id });
+                        }
+                    }
+                }
+
                 const st = lp.SemanticTree{
-                    .dom_node = self.page.document.asNode(),
+                    .dom_node = root_node,
                     .registry = self.registry.?,
                     .page = self.page,
                     .arena = self.arena.?,
                     .prune = true,
+                    .max_depth = self.maxDepth orelse std.math.maxInt(u32) - 1,
                 };
 
                 st.textStringify(w) catch |err| {
@@ -328,9 +344,13 @@ fn handleLinks(server: *Server, arena: std.mem.Allocator, id: std.json.Value, ar
 fn handleSemanticTree(server: *Server, arena: std.mem.Allocator, id: std.json.Value, arguments: ?std.json.Value) !void {
     const TreeParams = struct {
         url: ?[:0]const u8 = null,
+        backendNodeId: ?u32 = null,
+        maxDepth: ?u32 = null,
     };
+    var tree_args: TreeParams = .{};
     if (arguments) |args_raw| {
         if (std.json.parseFromValueLeaky(TreeParams, arena, args_raw, .{ .ignore_unknown_fields = true })) |args| {
+            tree_args = args;
             if (args.url) |u| {
                 try performGoto(server, u, id);
             }
@@ -341,7 +361,7 @@ fn handleSemanticTree(server: *Server, arena: std.mem.Allocator, id: std.json.Va
     };
 
     const content = [_]protocol.TextContent(ToolStreamingText){.{
-        .text = .{ .page = page, .action = .semantic_tree, .registry = &server.node_registry, .arena = arena },
+        .text = .{ .page = page, .action = .semantic_tree, .registry = &server.node_registry, .arena = arena, .backendNodeId = tree_args.backendNodeId, .maxDepth = tree_args.maxDepth },
     }};
     try server.sendResult(id, protocol.CallToolResult(ToolStreamingText){ .content = &content });
 }