diff --git a/lib/bbs.rb b/lib/bbs.rb
index 8d6e4fc..0e79801 100644
--- a/lib/bbs.rb
+++ b/lib/bbs.rb
@@ -20,6 +20,12 @@ require_relative 'bbs/focus_manager'
 require_relative 'bbs/menu'
 require_relative 'bbs/statusbar'
 require_relative 'bbs/dialogs'
+require_relative 'bbs/markdown'
+require_relative 'bbs/windows/button_bar'
+require_relative 'bbs/windows/info'
+require_relative 'bbs/windows/form'
+require_relative 'bbs/windows/master_detail'
+require_relative 'bbs/windows/stream'
 require_relative 'bbs/application'
 require_relative 'bbs/tui'
 require_relative 'bbs/tui_runner'
diff --git a/lib/bbs/application.rb b/lib/bbs/application.rb
index ebeda21..1ef0f61 100644
--- a/lib/bbs/application.rb
+++ b/lib/bbs/application.rb
@@ -125,14 +125,11 @@ module BBS
       @running = false
     end
 
-    # Periodic tick: notify on_tick callback and any window that defines
-    # a public @tick method (used by chat for incoming messages).
+    # Periodic tick: notify on_tick callback and let each open window pull
+    # any asynchronous updates by overriding BBS::Window#tick.
     def tick!
       @on_tick&.call(self)
-      @windows.each do |w|
-        poll = w.instance_variable_get(:@chat_poll)
-        poll&.call
-      end
+      @windows.each { |w| w.tick(self) }
     end
 
     def stop! = (@running = false)
diff --git a/lib/bbs/markdown.rb b/lib/bbs/markdown.rb
new file mode 100644
index 0000000..e3a5907
--- /dev/null
+++ b/lib/bbs/markdown.rb
@@ -0,0 +1,146 @@
+# frozen_string_literal: true
+
+require_relative 'frame_buffer'
+
+module BBS
+  # Markdown → ANSI line array renderer.
+  #
+  #   BBS::Markdown.to_lines(text, width:, theme:)
+  #
+  # Returns an array of strings (one per terminal line) with embedded ANSI SGR
+  # codes — suitable for BBS::Widgets::ScrollView. Each inline span ends with
+  # the theme :text SGR so that trailing text keeps the right background.
+  module Markdown
+    module_function
+
+    def to_lines(text, width:, theme:)
+      styles = {
+        base:   theme[:text],
+        h1:     theme[:text_bright],
+        h2:     theme[:accent],
+        h3:     theme[:label],
+        bold:   theme[:text_bright],
+        italic: theme[:text_dim],
+        code:   theme[:label],
+        link:   theme[:accent],
+        quote:  theme[:text_dim],
+        bullet: theme[:accent],
+        rule:   theme[:label],
+      }
+      result    = []
+      paragraph = []
+      in_code   = false
+      base      = styles[:base]
+
+      flush_paragraph = lambda do
+        next if paragraph.empty?
+        joined = paragraph.join(' ').gsub(/\s+/, ' ').strip
+        FrameBuffer.wrap_ansi(inline(joined, styles, base), width).each { |l| result << l }
+        paragraph.clear
+      end
+
+      text.to_s.split(/\r?\n/).each do |line|
+        if line.lstrip.start_with?('```')
+          flush_paragraph.call
+          in_code = !in_code
+          next
+        end
+
+        if in_code
+          flush_paragraph.call
+          clipped = FrameBuffer.clip_ansi(line, width)
+          result << "#{styles[:code]}#{clipped}#{base}"
+          next
+        end
+
+        if line.strip.empty?
+          flush_paragraph.call
+          result << ''
+          next
+        end
+
+        if (m = line.match(/\A([#]{1,6})\s+(.+?)\s*#*\s*\z/))
+          level   = m[1].length
+          heading = m[2].strip
+          flush_paragraph.call
+          style = level == 1 ? styles[:h1] : (level == 2 ? styles[:h2] : styles[:h3])
+          FrameBuffer.wrap_ansi(inline(heading, styles, base), width).each do |l|
+            result << "#{style}#{l}#{base}"
+          end
+          next
+        end
+
+        if line.match?(/\A\s*([-*_])\1{2,}\s*\z/)
+          flush_paragraph.call
+          result << "#{styles[:rule]}#{'─' * width}#{base}"
+          next
+        end
+
+        if (m = line.match(/\A\s*>\s?(.*)/))
+          content = m[1]
+          flush_paragraph.call
+          inner_w = [width - 2, 1].max
+          FrameBuffer.wrap_ansi(inline(content, styles, base), inner_w).each do |l|
+            result << "#{styles[:quote]}│ #{base}#{l}"
+          end
+          next
+        end
+
+        if (m = line.match(/\A(\s*)[-*+]\s+(.+)/))
+          indent = m[1].length
+          body   = m[2]
+          flush_paragraph.call
+          prefix_w = indent + 2
+          inner_w  = [width - prefix_w, 1].max
+          wrapped  = FrameBuffer.wrap_ansi(inline(body, styles, base), inner_w)
+          wrapped.each_with_index do |l, i|
+            pad = ' ' * indent
+            result << if i.zero?
+                        "#{pad}#{styles[:bullet]}•#{base} #{l}"
+                      else
+                        "#{' ' * prefix_w}#{l}"
+                      end
+          end
+          next
+        end
+
+        if (m = line.match(/\A(\s*)(\d+)\.\s+(.+)/))
+          indent = m[1].length
+          num    = m[2]
+          body   = m[3]
+          flush_paragraph.call
+          prefix  = "#{' ' * indent}#{num}. "
+          inner_w = [width - prefix.length, 1].max
+          wrapped = FrameBuffer.wrap_ansi(inline(body, styles, base), inner_w)
+          wrapped.each_with_index do |l, i|
+            result << if i.zero?
+                        "#{' ' * indent}#{styles[:bullet]}#{num}.#{base} #{l}"
+                      else
+                        "#{' ' * prefix.length}#{l}"
+                      end
+          end
+          next
+        end
+
+        paragraph << line.strip
+      end
+
+      flush_paragraph.call
+      result
+    end
+
+    def inline(text, styles, base_sgr)
+      s = text.to_s
+      s = s.gsub(/\[([^\]]+)\]\(([^)]+)\)/) { "#{styles[:link]}#{::Regexp.last_match(1)}#{base_sgr}" }
+      s = s.gsub(/`([^`]+)`/) { "#{styles[:code]}#{::Regexp.last_match(1)}#{base_sgr}" }
+      s = s.gsub(/\*\*([^*]+)\*\*/) { "#{styles[:bold]}#{::Regexp.last_match(1)}#{base_sgr}" }
+      s = s.gsub(/(?<![A-Za-z0-9*])\*([^*\s][^*]*?[^*\s]|\S)\*(?![A-Za-z0-9*])/) do
+        "#{styles[:italic]}#{::Regexp.last_match(1)}#{base_sgr}"
+      end
+      s = s.gsub(/(?<![A-Za-z0-9_])_([^_\s][^_]*?[^_\s]|\S)_(?![A-Za-z0-9_])/) do
+        "#{styles[:italic]}#{::Regexp.last_match(1)}#{base_sgr}"
+      end
+      s.gsub(/\\([\\`*_{}\[\]()#+\-.!>])/) { ::Regexp.last_match(1) }
+    end
+  end
+end
diff --git a/lib/bbs/window.rb b/lib/bbs/window.rb
index efbe3e3..1b5a76b 100644
--- a/lib/bbs/window.rb
+++ b/lib/bbs/window.rb
@@ -84,5 +84,9 @@ module BBS
       @on_close&.call(self)
       :close_window
     end
+
+    # Called once per Application idle tick (~1s). Override in subclasses that
+    # need to poll for asynchronous updates (e.g. BBS::Windows::Stream).
+    def tick(app); end
   end
 end
diff --git a/lib/bbs/windows/button_bar.rb b/lib/bbs/windows/button_bar.rb
new file mode 100644
index 0000000..f2b83fe
--- /dev/null
+++ b/lib/bbs/windows/button_bar.rb
@@ -0,0 +1,98 @@
+# frozen_string_literal: true
+
+require_relative '../widgets'
+
+module BBS
+  module Windows
+    # Lays out a row of buttons at the bottom of a window.
+    #
+    # Button descriptor:
+    #   { key:, label:, on_click:, primary:, cancel:, align:, keep_open: }
+    #
+    # `on_click` receives the BBS::Window as its only argument and may return
+    # :keep to keep the window open. Any other return value (or nil) causes
+    # the window to be closed after the handler.
+    #
+    # `primary: true` gets initial focus on the button.
+    # `cancel: true` is informational only — ESC closes the window through the
+    # standard Window#close_key path. If you also want a cancel-specific side
+    # effect on ESC, set `window.on_close = ...` manually.
+    # `align: :left | :right | :center` — default is :center for a single
+    # button, :right otherwise. Left-aligned buttons stack from the left edge;
+    # right-aligned buttons stack flush against the right edge in declaration
+    # order (so the last right-aligned button sits closest to the edge).
+    module ButtonBar
+      module_function
+
+      # Returns { widgets:, primary:, by_key: }.
+      def attach(window, app, descriptors)
+        return { widgets: [], primary: nil, by_key: {} } if descriptors.nil? || descriptors.empty?
+
+        widgets = descriptors.map do |d|
+          BBS::Widgets::Button.new(label: d[:label], on_click: build_handler(window, app, d))
+        end
+
+        default_align = descriptors.length == 1 ? :center : :right
+        aligns        = descriptors.map { |d| d[:align] || default_align }
+
+        row_y    = window.bounds.y + window.bounds.height - 2
+        left_x0  = window.bounds.x + 2
+        right_x1 = window.bounds.x + window.bounds.width - 2
+        win_x0   = window.bounds.x
+        win_w    = window.bounds.width
+
+        x = left_x0
+        widgets.each_with_index do |w, i|
+          next unless aligns[i] == :left
+          bw = button_width(w)
+          w.layout(x, row_y, bw, 1)
+          x += bw + 1
+        end
+
+        right_indices = aligns.each_index.select { |i| aligns[i] == :right }
+        total_right   = right_indices.sum { |i| button_width(widgets[i]) + 1 } - 1
+        total_right   = [total_right, 0].max
+        x = right_x1 - total_right + 1
+        right_indices.each do |i|
+          bw = button_width(widgets[i])
+          widgets[i].layout(x, row_y, bw, 1)
+          x += bw + 1
+        end
+
+        center_indices = aligns.each_index.select { |i| aligns[i] == :center }
+        total_center   = center_indices.sum { |i| button_width(widgets[i]) + 1 } - 1
+        total_center   = [total_center, 0].max
+        x = win_x0 + (win_w - total_center) / 2
+        center_indices.each do |i|
+          bw = button_width(widgets[i])
+          widgets[i].layout(x, row_y, bw, 1)
+          x += bw + 1
+        end
+
+        widgets.each { |w| window.add(w) }
+
+        primary_idx = descriptors.index { |d| d[:primary] }
+        primary     = primary_idx ? widgets[primary_idx] : nil
+
+        by_key = {}
+        descriptors.each_with_index { |d, i| by_key[d[:key]] = widgets[i] if d[:key] }
+
+        { widgets: widgets, primary: primary, by_key: by_key }
+      end
+
+      def button_width(button)
+        "[ #{button.display_label} ]".length
+      end
+
+      def build_handler(window, app, descriptor)
+        on_click  = descriptor[:on_click]
+        keep_open = descriptor[:keep_open]
+        lambda do |_btn|
+          result = on_click&.call(window)
+          app.close_window(window) unless keep_open || result == :keep
+          :handled
+        end
+      end
+    end
+  end
+end
diff --git a/lib/bbs/windows/form.rb b/lib/bbs/windows/form.rb
new file mode 100644
index 0000000..35e80e8
--- /dev/null
+++ b/lib/bbs/windows/form.rb
@@ -0,0 +1,216 @@
+# frozen_string_literal: true
+
+require_relative '../window'
+require_relative '../widgets'
+require_relative 'button_bar'
+
+module BBS
+  module Windows
+    # A form dialog with labeled input rows, optional textarea, and a status
+    # line for inline validation feedback.
+    #
+    #   BBS::Windows::Form.open(app,
+    #     title: " Profile — #{u} ", width: 64,
+    #     fields: [
+    #       { key: :signature, label: 'Signature', value: '...' },
+    #       { key: :location,  label: 'Location',  value: '...' },
+    #       { key: :notes,     label: 'Notes',     value: '...' },
+    #     ],
+    #     on_submit: ->(values, form) {
+    #       service.update(values); :close
+    #     }
+    #   )
+    #
+    # Field descriptor:
+    #   { key:, label:, value:, type:, max_length:, placeholder:, password:, rows: }
+    #
+    # Field types:
+    #   :input    (default) — single-line TextInput; label on left.
+    #   :textarea           — multi-line TextArea; full width, label ignored.
+    #   :checkbox           — Checkbox; label is part of the widget.
+    #
+    # on_submit receives `(values_hash, self)`. Return :keep to keep the
+    # window open (e.g., after `form.error('...')`); any other value closes.
+    #
+    # `hint:` shows an info line above the fields (no label/value, no input).
+    class Form < Window
+      DEFAULT_PADDING = { sides: 2, top: 1, bottom: 2 }.freeze
+
+      def self.open(app, **kw)
+        new(app: app, **kw).tap(&:attach)
+      end
+
+      attr_reader :status_label
+
+      def initialize(app:, title:, fields:, on_submit:,
+                     hint: nil, width: 60, height: nil,
+                     submit_label: '&Save', cancel_label: '&Cancel',
+                     padding: nil, on_cancel: nil)
+        super(title: title, modal: true)
+        self.theme = app.theme
+        @app          = app
+        @fields       = fields
+        @hint         = hint
+        @on_submit    = on_submit
+        @on_cancel    = on_cancel
+        @submit_label = submit_label
+        @cancel_label = cancel_label
+        @width        = width
+        @height       = height
+        @padding      = DEFAULT_PADDING.merge(padding || {})
+        @widgets      = {}
+        build
+      end
+
+      def attach
+        @app.open_window(self)
+        reset_focus
+        first = @fields.first
+        focus_manager.focus(@widgets[first[:key]]) if first && @widgets[first[:key]]
+        self
+      end
+
+      def values
+        @fields.each_with_object({}) { |f, h| h[f[:key]] = field_value(f) }
+      end
+
+      def error(text)
+        return unless @status_label
+        @status_label.text      = text.to_s
+        @status_label.style_key = :error
+      end
+
+      def info(text)
+        return unless @status_label
+        @status_label.text      = text.to_s
+        @status_label.style_key = :input_label
+      end
+
+      def clear_status
+        @status_label&.text = ''
+      end
+
+      private
+
+      def field_value(field)
+        widget = @widgets[field[:key]]
+        return nil unless widget
+        return widget.checked if field[:type] == :checkbox
+        widget.value
+      end
+
+      def build
+        w = [@width, @app.cols - 4].min
+        heights = @fields.map { |f| natural_field_height(f) }
+
+        hint_block   = @hint ? 2 : 0           # hint + spacer
+        spacing      = [@fields.length - 1, 0].max
+        status_block = 1
+        buttons_block = 2                       # spacer + button row
+
+        h_auto = @padding[:top] + hint_block + heights.sum + spacing +
+                 1 + status_block + buttons_block + @padding[:bottom]
+        h = @height || h_auto
+        h = [h, @app.rows - 4].min
+
+        # If explicit height + exactly one textarea without :rows, expand it.
+        if @height
+          ta_indices = @fields.each_index.select do |i|
+            @fields[i][:type] == :textarea && !@fields[i][:rows]
+          end
+          if ta_indices.length == 1
+            idx        = ta_indices.first
+            fixed_rest = heights.each_with_index.reject { |_, i| i == idx }.sum { |row, _| row }
+            available  = h - @padding[:top] - @padding[:bottom] - hint_block -
+                         spacing - 1 - status_block - buttons_block
+            heights[idx] = [available - fixed_rest, 1].max
+          end
+        end
+
+        x = (@app.cols - w) / 2 + 1
+        y = (@app.rows - h) / 2 + 1
+        layout(x, y, w, h)
+
+        inner_x = bounds.x + @padding[:sides]
+        inner_w = w - @padding[:sides] * 2
+        row_y   = bounds.y + @padding[:top]
+
+        if @hint
+          hint = BBS::Widgets::Label.new(text: @hint, style_key: :input_label)
+          hint.layout(inner_x, row_y, inner_w, 1)
+          add(hint)
+          row_y += 2
+        end
+
+        label_w = compute_label_width
+
+        @fields.each_with_index do |f, i|
+          place_field(f, heights[i], inner_x, inner_w, row_y, label_w)
+          row_y += heights[i] + 1
+        end
+
+        @status_label = BBS::Widgets::Label.new(text: '', style_key: :error)
+        @status_label.layout(inner_x, bounds.y + h - 3, inner_w, 1)
+        add(@status_label)
+
+        ButtonBar.attach(self, @app, [
+          { key: :submit, label: @submit_label, primary: true,
+            on_click:  ->(_w) { @on_submit ? @on_submit.call(values, self) : :close } },
+          { key: :cancel, label: @cancel_label, cancel: true,
+            on_click:  ->(_w) { @on_cancel&.call(self) } }
+        ])
+      end
+
+      def natural_field_height(field)
+        case field[:type]
+        when :textarea then field[:rows] || 6
+        else 1
+        end
+      end
+
+      def compute_label_width
+        with_labels = @fields.select { |f| f[:label] && f[:type] != :textarea && f[:type] != :checkbox }
+        return 0 if with_labels.empty?
+        max = with_labels.map { |f| f[:label].to_s.length }.max
+        [max + 1, 16].min.clamp(8, 16)
+      end
+
+      def place_field(field, height, inner_x, inner_w, y, label_w)
+        case field[:type]
+        when :textarea
+          widget = BBS::Widgets::TextArea.new(
+            value: field[:value].to_s,
+            max_length: field[:max_length] || 8_000
+          )
+          widget.layout(inner_x, y, inner_w, height)
+        when :checkbox
+          widget = BBS::Widgets::Checkbox.new(
+            label: field[:label].to_s,
+            checked: field[:value] ? true : false
+          )
+          widget.layout(inner_x, y, inner_w, 1)
+        else
+          if field[:label]
+            label = BBS::Widgets::Label.new(text: field[:label].to_s, style_key: :input_label)
+            label.layout(inner_x, y, label_w, 1)
+            add(label)
+            input_x = inner_x + label_w + 2
+            input_w = inner_w - label_w - 2
+          else
+            input_x = inner_x
+            input_w = inner_w
+          end
+          widget = BBS::Widgets::TextInput.new(
+            value: field[:value].to_s,
+            placeholder: field[:placeholder].to_s,
+            max_length: field[:max_length] || 256,
+            password: field[:password] ? true : false
+          )
+          widget.layout(input_x, y, input_w, 1)
+        end
+        add(widget)
+        @widgets[field[:key]] = widget
+      end
+    end
+  end
+end
diff --git a/lib/bbs/windows/info.rb b/lib/bbs/windows/info.rb
new file mode 100644
index 0000000..142f3be
--- /dev/null
+++ b/lib/bbs/windows/info.rb
@@ -0,0 +1,212 @@
+# frozen_string_literal: true
+
+require_relative '../window'
+require_relative '../widgets'
+require_relative '../frame_buffer'
+require_relative 'button_bar'
+
+module BBS
+  module Windows
+    # A centered modal dialog for messages, splash screens, info displays.
+    #
+    #   BBS::Windows::Info.open(app,
+    #     title: ' Welcome ',
+    #     width: 70, height: 17,
+    #     body: [
+    #       { text: banner_line, style: :accent },
+    #       "plain label with optional \e[1;33mraw ANSI\e[0m",
+    #       :spacer,
+    #       :rule,
+    #       { kv: [['Online users', '5'], ['Ruby', RUBY_VERSION]] },
+    #     ],
+    #     buttons: [{ label: '&Continue', primary: true }]
+    #   )
+    #
+    # When `scroll: true`, body items are flattened into a single ScrollView
+    # filling the inner area. Use this for long, paginated content lists.
+    #
+    # Body item types:
+    #   String                              → label with :window_text style
+    #   :spacer | '' | nil                  → blank row
+    #   :rule                               → horizontal ─── line
+    #   { text:, style:, align: }           → styled label
+    #   { kv: [[k, v], ...], label_width: } → key/value rows
+    #   { widget:, height: }                → arbitrary widget (non-scroll only)
+    #   BBS::Widget                         → as-is, 1 row (non-scroll only)
+    #
+    # Default buttons: a single centered `[ &Close ]` if `buttons:` is nil.
+    class Info < Window
+      DEFAULT_BUTTON  = [{ label: '&Close', cancel: true }].freeze
+      DEFAULT_PADDING = { sides: 2, top: 1, bottom: 2 }.freeze
+
+      def self.open(app, **kw)
+        new(app: app, **kw).tap(&:attach)
+      end
+
+      attr_reader :scroll_view
+
+      def initialize(app:, title:, body: [], buttons: nil, width: 60, height: nil,
+                     scroll: false, padding: nil)
+        super(title: title, modal: true)
+        self.theme = app.theme
+        @app     = app
+        @body    = body
+        @buttons = buttons.nil? ? DEFAULT_BUTTON.dup : Array(buttons)
+        @scroll  = scroll
+        @width   = width
+        @height  = height
+        @padding = DEFAULT_PADDING.merge(padding || {})
+        build
+      end
+
+      def attach
+        @app.open_window(self)
+        reset_focus
+        focus_manager.focus(@primary_button) if @primary_button
+        self
+      end
+
+      private
+
+      def build
+        button_h = @buttons.any? ? 2 : 0
+        body_rows = @scroll ? 10 : @body.sum { |it| item_rows(it) }
+        h = @height || (@padding[:top] + body_rows + button_h + @padding[:bottom])
+        w = [@width, @app.cols - 4].min
+        h = [h, @app.rows - 4].min
+        x = (@app.cols - w) / 2 + 1
+        y = (@app.rows - h) / 2 + 1
+        layout(x, y, w, h)
+
+        inner_w = w - @padding[:sides] * 2
+        inner_x = bounds.x + @padding[:sides]
+        inner_y = bounds.y + @padding[:top]
+        body_h  = h - @padding[:top] - @padding[:bottom] - button_h
+        body_h  = [body_h, 0].max
+
+        if @scroll
+          place_scroll_body(inner_x, inner_y, inner_w, body_h)
+        else
+          place_static_body(inner_x, inner_y, inner_w)
+        end
+
+        @primary_button = ButtonBar.attach(self, @app, @buttons)[:primary]
+      end
+
+      def item_rows(item)
+        case item
+        when :spacer, :rule, '', nil then 1
+        when String                  then 1
+        when Hash
+          return item[:kv].length          if item[:kv]
+          return item[:height] || 1        if item[:widget]
+          1
+        when BBS::Widget
+          h = item.bounds.height
+          h.positive? ? h : 1
+        else 1
+        end
+      end
+
+      def place_scroll_body(x, y, w, h)
+        lines = []
+        @body.each { |item| append_scroll_lines(lines, item, w) }
+        @scroll_view = BBS::Widgets::ScrollView.new(lines: lines)
+        @scroll_view.layout(x, y, w, h)
+        add(@scroll_view)
+      end
+
+      def append_scroll_lines(lines, item, width)
+        base = theme[:text]
+        case item
+        when :spacer, '', nil
+          lines << ''
+        when :rule
+          lines << "#{theme[:label]}#{'─' * width}#{base}"
+        when String
+          lines << item
+        when Hash
+          if item[:kv]
+            kw = item[:label_width] || default_kv_label_width(item[:kv])
+            item[:kv].each do |k, v|
+              lines << "#{theme[:input_label]}#{k.to_s.ljust(kw)}#{base}  #{v}"
+            end
+          elsif item[:text]
+            sgr = item[:style] ? theme[item[:style]] : base
+            lines << "#{sgr}#{item[:text]}#{base}"
+          end
+        when BBS::Widget
+          raise ArgumentError, 'scroll mode does not support widget body items'
+        end
+      end
+
+      def place_static_body(x, y, w)
+        row = 0
+        @body.each { |item| row += place_static_item(item, x, y + row, w) }
+      end
+
+      def place_static_item(item, x, y, w)
+        case item
+        when :spacer, '', nil
+          1
+        when :rule
+          label = BBS::Widgets::Label.new(text: '─' * w, style_key: :label)
+          label.layout(x, y, w, 1)
+          add(label)
+          1
+        when String
+          label = BBS::Widgets::Label.new(text: item, style_key: :window_text)
+          label.layout(x, y, w, 1)
+          add(label)
+          1
+        when Hash
+          place_static_hash(item, x, y, w)
+        when BBS::Widget
+          h = item.bounds.height.positive? ? item.bounds.height : 1
+          item.layout(x, y, w, h)
+          add(item)
+          h
+        else
+          1
+        end
+      end
+
+      def place_static_hash(item, x, y, w)
+        if item[:kv]
+          kw = item[:label_width] || default_kv_label_width(item[:kv])
+          item[:kv].each_with_index do |(k, v), i|
+            label = BBS::Widgets::Label.new(text: k.to_s.ljust(kw), style_key: :input_label)
+            label.layout(x, y + i, kw, 1)
+            add(label)
+            value = BBS::Widgets::Label.new(text: v.to_s, style_key: :window_text)
+            value.layout(x + kw + 2, y + i, w - kw - 2, 1)
+            add(value)
+          end
+          item[:kv].length
+        elsif item[:widget]
+          wd = item[:widget]
+          h  = item[:height] || (wd.bounds.height.positive? ? wd.bounds.height : 1)
+          wd.layout(x, y, w, h)
+          add(wd)
+          h
+        elsif item[:text]
+          label = BBS::Widgets::Label.new(
+            text:      item[:text],
+            style_key: item[:style] || :window_text,
+            align:     item[:align] || :left
+          )
+          label.layout(x, y, w, 1)
+          add(label)
+          1
+        else
+          1
+        end
+      end
+
+      def default_kv_label_width(pairs)
+        max = pairs.map { |k, _| k.to_s.length }.max || 0
+        [max + 1, 16].min.clamp(8, 16)
+      end
+    end
+  end
+end
diff --git a/lib/bbs/windows/master_detail.rb b/lib/bbs/windows/master_detail.rb
new file mode 100644
index 0000000..3b8e9ae
--- /dev/null
+++ b/lib/bbs/windows/master_detail.rb
@@ -0,0 +1,128 @@
+# frozen_string_literal: true
+
+require_relative '../window'
+require_relative '../widgets'
+require_relative 'button_bar'
+
+module BBS
+  module Windows
+    # A two-pane browser: left ListBox of items, right ScrollView of details.
+    # Selecting an item in the list reloads the detail pane.
+    #
+    #   BBS::Windows::MasterDetail.open(app,
+    #     title: ' Game Catalog ',
+    #     items: services[:games].all,
+    #     item_label: ->(g) { g.title },
+    #     list_width: 30,
+    #     render_detail: ->(game, width) { GameCard.lines(game, width) },
+    #     actions: [
+    #       { label: '&New', on_click: ->(win) { ... } }
+    #     ],
+    #     bottom_meta: ->(item) { "...optional 1-line meta..." }
+    #   )
+    #
+    # `render_detail` is called with `(item, width)` whenever the selection
+    # changes and on first paint. It must return an Array of strings (each one
+    # is one rendered line; ANSI is supported). Returning nil shows nothing.
+    #
+    # `bottom_meta` is optional; if given, it's a `->(item) { text }` lambda
+    # for a single info line below the detail pane.
+    #
+    # `actions:` are extra buttons (right-aligned by default). A `Close` button
+    # is always appended on the right unless the caller suppresses it via
+    # `close_button: false`.
+    class MasterDetail < Window
+      def self.open(app, **kw)
+        new(app: app, **kw).tap(&:attach)
+      end
+
+      attr_reader :list_widget, :detail_view, :meta_label
+
+      def initialize(app:, title:, items:, item_label:, render_detail:,
+                     list_width: nil, bottom_meta: nil, actions: nil,
+                     close_button: true, close_label: '&Close',
+                     empty_message: '  (empty)',
+                     width: nil, height: nil)
+        super(title: title, modal: true)
+        self.theme = app.theme
+        @app           = app
+        @items         = items
+        @item_label    = item_label
+        @render_detail = render_detail
+        @bottom_meta   = bottom_meta
+        @actions       = (actions || []).dup
+        @actions << { label: close_label, cancel: true } if close_button
+        @list_width    = list_width
+        @empty_message = empty_message
+        @width         = width
+        @height        = height
+        build
+      end
+
+      def attach
+        @app.open_window(self)
+        reset_focus
+        focus_manager.focus(@list_widget) if @list_widget
+        reload_detail
+        self
+      end
+
+      def reload_detail
+        item = @list_widget&.selected_item
+        if item.nil?
+          @detail_view.lines  = [@empty_message]
+          @detail_view.scroll = 0
+          @meta_label.text    = '' if @meta_label
+        else
+          lines = @render_detail.call(item, @detail_view.bounds.width - 1)
+          @detail_view.lines  = Array(lines)
+          @detail_view.scroll = 0
+          @meta_label.text    = @bottom_meta.call(item) if @meta_label && @bottom_meta
+        end
+      end
+
+      private
+
+      def build
+        w = @width  || @app.cols - 4
+        h = @height || @app.rows - 6
+        x = (@app.cols - w) / 2 + 1
+        y = (@app.rows - h) / 2 + 1
+        layout(x, y, w, h)
+
+        has_buttons = !@actions.empty?
+        has_meta    = !@bottom_meta.nil?
+        panel_h     = h - 4 - (has_meta ? 1 : 0) - (has_buttons ? 1 : 0)
+        panel_h     = [panel_h, 3].max
+
+        list_w = @list_width || [(w / 3).clamp(20, 40), w - 10].min
+        list_x = bounds.x + 2
+        list_y = bounds.y + 2
+
+        @list_widget = BBS::Widgets::ListBox.new(
+          items: @items,
+          label: ->(item) { "  #{@item_label.call(item)}".ljust(list_w) }
+        )
+        @list_widget.layout(list_x, list_y, list_w, panel_h)
+        add(@list_widget)
+
+        detail_x = list_x + list_w + 2
+        detail_w = bounds.width - list_w - 5
+        @detail_view = BBS::Widgets::ScrollView.new(lines: [])
+        @detail_view.layout(detail_x, list_y, detail_w, panel_h)
+        add(@detail_view)
+
+        if has_meta
+          meta_y = bounds.y + h - (has_buttons ? 3 : 2)
+          @meta_label = BBS::Widgets::Label.new(text: '', style_key: :input_label)
+          @meta_label.layout(bounds.x + 2, meta_y, bounds.width - 4, 1)
+          add(@meta_label)
+        end
+
+        @list_widget.on_select = ->(_, _) { reload_detail }
+
+        ButtonBar.attach(self, @app, @actions)
+      end
+    end
+  end
+end
diff --git a/lib/bbs/windows/stream.rb b/lib/bbs/windows/stream.rb
new file mode 100644
index 0000000..3d1811c
--- /dev/null
+++ b/lib/bbs/windows/stream.rb
@@ -0,0 +1,106 @@
+# frozen_string_literal: true
+
+require_relative '../window'
+require_relative '../widgets'
+require_relative 'button_bar'
+
+module BBS
+  module Windows
+    # A live stream window: scrollable history + single-line input + poll.
+    #
+    #   BBS::Windows::Stream.open(app,
+    #     title: ' Live Chat ',
+    #     initial_lines: services[:chat].history.map { |l| fmt(l) },
+    #     placeholder: 'Type a message and press Enter…',
+    #     on_submit: ->(text, app) {
+    #       services[:chat].broadcast(username, text.strip)
+    #     },
+    #     on_poll: ->(app) {
+    #       services[:chat].drain(app.session_id).map { |l| fmt(l) }
+    #     }
+    #   )
+    #
+    # `on_submit(text, app)` is called when the user presses Enter on a
+    # non-empty input. The input is cleared automatically afterwards unless
+    # the handler returns `:keep`.
+    #
+    # `on_poll(app)` is invoked from the application's idle tick (~1s). It
+    # should return an Array of new lines to append (or nil/[]).
+    class Stream < Window
+      def self.open(app, **kw)
+        new(app: app, **kw).tap(&:attach)
+      end
+
+      attr_reader :history, :input
+
+      def initialize(app:, title:, initial_lines: [], placeholder: '',
+                     on_submit: nil, on_poll: nil, buffer_size: 500,
+                     width: nil, height: nil,
+                     close_button: true, close_label: '&Close')
+        super(title: title, modal: true)
+        self.theme = app.theme
+        @app           = app
+        @initial_lines = initial_lines
+        @placeholder   = placeholder
+        @on_submit     = on_submit
+        @on_poll       = on_poll
+        @buffer_size   = buffer_size
+        @width         = width
+        @height        = height
+        @close_button  = close_button
+        @close_label   = close_label
+        build
+      end
+
+      def attach
+        @app.open_window(self)
+        reset_focus
+        focus_manager.focus(@input)
+        self
+      end
+
+      def tick(_app)
+        return unless @on_poll
+        new_lines = @on_poll.call(@app)
+        return if new_lines.nil? || new_lines.empty?
+        @history.lines  = (@history.lines + Array(new_lines)).last(@buffer_size)
+        @history.scroll = [@history.lines.size - @history.bounds.height, 0].max
+      end
+
+      private
+
+      def build
+        w = @width  || @app.cols - 8
+        h = @height || @app.rows - 6
+        x = (@app.cols - w) / 2 + 1
+        y = (@app.rows - h) / 2 + 1
+        layout(x, y, w, h)
+
+        inner_x = bounds.x + 2
+        inner_w = bounds.width - 4
+
+        @history = BBS::Widgets::ScrollView.new(lines: @initial_lines)
+        @history.layout(inner_x, bounds.y + 1, inner_w, h - 4)
+        @history.scroll = [@history.lines.size - @history.bounds.height, 0].max
+        add(@history)
+
+        @input = BBS::Widgets::TextInput.new(placeholder: @placeholder)
+        @input.on_submit = method(:handle_input_submit)
+        @input.layout(inner_x, bounds.y + h - 3, inner_w, 1)
+        add(@input)
+
+        if @close_button
+          ButtonBar.attach(self, @app, [{ label: @close_label, cancel: true }])
+        end
+      end
+
+      def handle_input_submit(value, _input)
+        text = value.to_s
+        return :handled if text.strip.empty?
+        result = @on_submit&.call(text, @app)
+        @input.value = '' unless result == :keep
+        :handled
+      end
+    end
+  end
+end