diff --git a/backends/imgui_impl_roblox.lua b/backends/imgui_impl_roblox.lua
index a8a8010..63d2def 100644
--- a/backends/imgui_impl_roblox.lua
+++ b/backends/imgui_impl_roblox.lua
@@ -95,7 +95,8 @@ end
 -- Games can't touch the OS clipboard, so copy/paste only works inside ImGui
 local clipboard = ""
 local function ImGui_ImplRoblox_PlatformSetClipboardText(ctx, text) clipboard = text end
-local function ImGui_ImplRoblox_PlatformGetClipboardText(ctx) return clipboard end
+local proxy_focused = false
+local function ImGui_ImplRoblox_PlatformGetClipboardText(ctx) if proxy_focused then return "" end return clipboard end
 
 ---------------------------------------------------------
 -- FILE SYSTEM (in-memory, Roblox has no file access)
@@ -1089,17 +1090,21 @@ function ImGui_ImplRoblox_Init(parent, render_scale)
         if button then
             io:AddMouseSourceEvent(ImGuiMouseSource.Mouse)
             io:AddMouseButtonEvent(button, true)
-        elseif input.UserInputType == Enum.UserInputType.Keyboard and not game_processed then
+        elseif input.UserInputType == Enum.UserInputType.Keyboard and (not game_processed or proxy_focused) then
             local ctrl, shift, alt = ImGui_ImplRoblox_UpdateKeyModifiers()
             local key = KEY_MAP[input.KeyCode]
             if key then io:AddKeyEvent(key, true) end
+            if proxy_focused and (key == ImGuiKey.Backspace or key == ImGuiKey.Delete) then ImGui_ImplRoblox_GetBackendData().DeleteKeySeen = true end
 
             -- Text: printable ASCII keys, skipped while Ctrl/Alt are held (shortcuts)
             local v = input.KeyCode.Value
             if v >= 32 and v < 127 and not (ctrl or alt) then
                 local c = string.char(v)
                 if shift then c = SHIFTED[c] or c:upper() end
-                io:AddInputCharacter(string.byte(c))
+                -- While the proxy may own text input, hold the char: NewFrame uses the proxy's text if it changed
+                -- (correct layout/unicode), otherwise these. So typing works even if the proxy silently lost focus.
+                if proxy_focused then table.insert(ImGui_ImplRoblox_GetBackendData().PendingChars, string.byte(c))
+                else io:AddInputCharacter(string.byte(c)) end
             end
         end
     end)
@@ -1122,6 +1127,34 @@ function ImGui_ImplRoblox_Init(parent, render_scale)
         end
     end)
 
+    -- Text proxy: a hidden TextBox holds focus while an imgui text field is active, so the OS gives us typing (any
+    -- layout/unicode), paste (Ctrl+V) and copy/cut (Ctrl+C/X of the proxy's text = imgui's current selection).
+    local proxy = Instance.new("TextBox")
+    proxy.Name = "TextProxy"
+    proxy.BackgroundTransparency = 1
+    proxy.TextTransparency = 0 -- kept opaque but parked off screen: a transparent TextBox may not get native paste
+    proxy.BorderSizePixel = 0
+    proxy.Size = UDim2.fromOffset(200, 20)
+    proxy.Position = UDim2.fromOffset(-10000, -10000)
+    proxy.MultiLine = true
+    proxy.ClearTextOnFocus = false
+    proxy.TextEditable = true
+    proxy.Text = ""
+    proxy.Parent = gui
+    bd.Proxy, bd.ProxyText, bd.PendingChars = proxy, "", {}
+    -- Clicking elsewhere (or Roblox taking focus) ends the edit, like clicking outside the field in imgui.
+    -- (Text is polled in NewFrame instead of using Text changed signals: those are deferred in Roblox.)
+    connect(proxy.FocusLost, function()
+        if bd.ProxyDebug then print("[ImGui text proxy] FocusLost, mouse over imgui:", ImGui.GetIO().WantCaptureMouse) end
+        if bd.ProxyReleasing then return end
+        -- Roblox drops TextBox focus on any click, including clicks inside imgui (e.g. moving the cursor within the
+        -- same field). Those must not end the edit: just recapture next frame. Only a click outside imgui ends it.
+        if ImGui.GetIO().WantCaptureMouse then bd.ProxyLostId = nil; return end
+        bd.ProxyLostId = bd.ProxyActiveId -- don't recapture for the same field
+        local g = ImGui.GetCurrentContext()
+        if g and g.ActiveId ~= 0 and g.ActiveId == bd.ProxyActiveId then ImGui.ClearActiveID() end
+    end)
+
     connect(UserInputService.WindowFocused, function() ImGui.GetIO():AddFocusEvent(true) end)
     connect(UserInputService.WindowFocusReleased, function() ImGui.GetIO():AddFocusEvent(false) end)
 end
@@ -1164,6 +1197,86 @@ function ImGui_ImplRoblox_NewFrame()
         io:AddMousePosEvent(m.X * bd.Scale, m.Y * bd.Scale)
     end
 
+    -- Text proxy: focused while an imgui text field is active. proxy_focused only when Roblox really gave it focus,
+    -- otherwise the KeyCode fallback keeps typing working.
+    local proxy = bd.Proxy
+    local g = ImGui.GetCurrentContext()
+    local focused_box = UserInputService:GetFocusedTextBox()
+    if io.WantTextInput and g.ActiveId ~= 0 then
+        if g.ActiveId ~= bd.ProxyActiveId or g.ActiveIdIsJustActivated or g.IO.MouseClicked[0] then bd.ProxyActiveId = g.ActiveId; bd.ProxyLostId = nil end -- (re)clicking a field recaptures
+        local mouse_up = not (io.MouseDown[0] or io.MouseDown[1] or io.MouseDown[2])
+        if focused_box ~= proxy and mouse_up and bd.ProxyLostId ~= g.ActiveId and (focused_box == nil or not focused_box:IsDescendantOf(game)) then
+            bd.ProxyText = proxy.Text -- what it already holds is not new input (else re-typing it would collapse imgui's selection)
+            proxy:CaptureFocus()
+            focused_box = UserInputService:GetFocusedTextBox()
+            if bd.ProxyDebug then print("[ImGui text proxy] CaptureFocus ->", focused_box == proxy and "focused" or ("FAILED, focused = " .. tostring(focused_box))) end
+        end
+    elseif focused_box == proxy then
+        bd.ProxyReleasing = true
+        proxy:ReleaseFocus()
+        bd.ProxyReleasing = false
+        focused_box = nil
+    end
+    local was_focused = proxy_focused
+    proxy_focused = focused_box == proxy
+    local used_proxy_text = false
+    if proxy_focused then
+        -- 1) whatever the OS put in the proxy since last frame (typing, paste, cut) replaces imgui's selection
+        local text = proxy.Text
+        if text ~= bd.ProxyText and bd.ProxyDebug then print("[ImGui text proxy] text", string.format("%q", text), "was", string.format("%q", tostring(bd.ProxyText))) end
+        if text ~= bd.ProxyText and text ~= bd.ProxyLastRaw then -- (LastRaw: don't re-send if our reset hasn't applied yet)
+            bd.ProxyLastRaw = text
+            -- InputText ignores characters while Ctrl is held (upstream, so shortcuts don't type); a paste arrives with
+            -- Ctrl still down, so release Ctrl around the characters in the event queue.
+            local ctrl = io.KeyCtrl or UserInputService:IsKeyDown(Enum.KeyCode.LeftControl) or UserInputService:IsKeyDown(Enum.KeyCode.RightControl)
+            if ctrl then io:AddKeyEvent(ImGuiMod_Ctrl, false) end
+            local prev = bd.ProxyText or ""
+            if #text < #prev and prev:sub(1, #text) == text and text:sub(-1) ~= "\n" then
+                -- The TextBox deleted from its own text (Backspace/Delete; Roblox can't hold a real selection in it, so it
+                -- may remove just 1 char). Apply the deletion with imgui's own selection instead: one Backspace deletes
+                -- the whole imgui selection, or one char if none. Skipped if imgui already got the key event.
+                if not bd.DeleteKeySeen then io:AddKeyEvent(ImGuiKey.Backspace, true); io:AddKeyEvent(ImGuiKey.Backspace, false) end
+            elseif text ~= "\n" and text ~= "\r" and text ~= "\t" then -- Enter/Tab arrive as key events
+                local prev = bd.ProxyText or ""
+                if #text > 0 and (prev == "" or text:sub(1, #prev) ~= prev or #text <= #prev) then
+                    for _, cp in utf8.codes(text) do io:AddInputCharacter(cp) end
+                elseif #text > #prev then
+                    for _, cp in utf8.codes(text:sub(#prev + 1)) do io:AddInputCharacter(cp) end
+                end
+            end
+            if ctrl then io:AddKeyEvent(ImGuiMod_Ctrl, true) end
+            used_proxy_text = true
+            bd.ProxyText = nil
+        end
+        -- 2) mirror imgui's selection, fully selected, so the native Ctrl+C / Ctrl+X copy exactly that
+        local st = g.InputTextState
+        local sel = ""
+        if st and st.ID ~= 0 and st.ID == g.ActiveId and st.Stb and st:HasSelection() then
+            local a, b = math.min(st.Stb.select_start, st.Stb.select_end), math.max(st.Stb.select_start, st.Stb.select_end)
+            sel = ImGui._ByteArrayToString(st.TextA.Data, a, b) -- stb positions are 1-based in this port
+        end
+        if sel ~= bd.ProxyText then
+            proxy.Text = sel
+            bd.ProxyLastRaw = nil
+            bd.ProxyText = sel
+            if bd.ProxyDebug then print("[ImGui text proxy] mirror selection", string.format("%q", sel)) end
+        end
+        -- keep imgui's selection fully selected in the proxy, so Ctrl+C copies it and typing/Ctrl+V replaces it
+        local want_sel, want_cur = (#sel > 0) and 1 or -1, #sel + 1
+        if proxy.SelectionStart ~= want_sel then proxy.SelectionStart = want_sel end
+        if proxy.CursorPosition ~= want_cur then proxy.CursorPosition = want_cur end
+    end
+
+    bd.DeleteKeySeen = false
+
+    -- Held KeyCode chars: dropped if the proxy delivered the text, otherwise typed (proxy didn't really get the keys)
+    local pending = bd.PendingChars
+    if #pending > 0 then
+        if not used_proxy_text then for _, c in ipairs(pending) do io:AddInputCharacter(c) end end
+        table.clear(pending)
+    end
+    if bd.ProxyDebug and was_focused ~= proxy_focused then print("[ImGui text proxy] proxy_focused =", proxy_focused) end
+
     -- While the mouse is over imgui, make the tiles Active so Roblox stops passing clicks/wheel to the game (camera zoom etc.)
     local want = io.WantCaptureMouse
     if want ~= bd.TilesActive then
@@ -1204,6 +1317,7 @@ ImGui_ImplRoblox = {
     SetRenderScale = ImGui_ImplRoblox_SetRenderScale,
     SetRenderRate  = ImGui_ImplRoblox_SetRenderRate,
     SetOverlay     = ImGui_ImplRoblox_SetOverlay,
+    SetTextProxyDebug = function(on) ImGui_ImplRoblox_GetBackendData().ProxyDebug = on end, -- prints focus/text events
     CreateTexture  = ImGui_ImplRoblox_CreateTexture,
     DestroyTexture = ImGui_ImplRoblox_DestroyTexture,
     GetRenderScale = function() return ImGui_ImplRoblox_GetBackendData().Scale end,
diff --git a/build/ImGui.linemap.json b/build/ImGui.linemap.json
index d95d75f..6a77b25 100644
--- a/build/ImGui.linemap.json
+++ b/build/ImGui.linemap.json
@@ -1 +1 @@
-[[12, "imgui.lua"], [18472, "imgui_demo.lua"], [25757, "imgui_draw.lua"], [30995, "imgui_h.lua"], [33193, "imgui_impl_roblox.lua"], [34411, "imgui_impl_roblox_fonts.lua"], [40814, "imgui_internal.lua"], [43986, "imgui_tables.lua"], [48333, "imgui_widgets.lua"], [58088, "imstb_rectpack.lua"], [58534, "imstb_textedit.lua"], [59775, "imstb_truetype.lua"], [62243, "imstd_minstdio.lua"]]
\ No newline at end of file
+[[12, "imgui.lua"], [18472, "imgui_demo.lua"], [25757, "imgui_draw.lua"], [30995, "imgui_h.lua"], [33193, "imgui_impl_roblox.lua"], [34525, "imgui_impl_roblox_fonts.lua"], [40928, "imgui_internal.lua"], [44100, "imgui_tables.lua"], [48447, "imgui_widgets.lua"], [58202, "imstb_rectpack.lua"], [58648, "imstb_textedit.lua"], [59889, "imstb_truetype.lua"], [62357, "imstd_minstdio.lua"]]
\ No newline at end of file
diff --git a/build/ImGui.luau b/build/ImGui.luau
index 7a13cef..01045e6 100644
--- a/build/ImGui.luau
+++ b/build/ImGui.luau
@@ -33287,7 +33287,8 @@ end
 -- Games can't touch the OS clipboard, so copy/paste only works inside ImGui
 local clipboard = ""
 local function ImGui_ImplRoblox_PlatformSetClipboardText(ctx, text) clipboard = text end
-local function ImGui_ImplRoblox_PlatformGetClipboardText(ctx) return clipboard end
+local proxy_focused = false
+local function ImGui_ImplRoblox_PlatformGetClipboardText(ctx) if proxy_focused then return "" end return clipboard end
 
 ---------------------------------------------------------
 -- FILE SYSTEM (in-memory, Roblox has no file access)
@@ -34281,17 +34282,21 @@ function ImGui_ImplRoblox_Init(parent, render_scale)
         if button then
             io:AddMouseSourceEvent(ImGuiMouseSource.Mouse)
             io:AddMouseButtonEvent(button, true)
-        elseif input.UserInputType == Enum.UserInputType.Keyboard and not game_processed then
+        elseif input.UserInputType == Enum.UserInputType.Keyboard and (not game_processed or proxy_focused) then
             local ctrl, shift, alt = ImGui_ImplRoblox_UpdateKeyModifiers()
             local key = KEY_MAP[input.KeyCode]
             if key then io:AddKeyEvent(key, true) end
+            if proxy_focused and (key == ImGuiKey.Backspace or key == ImGuiKey.Delete) then ImGui_ImplRoblox_GetBackendData().DeleteKeySeen = true end
 
             -- Text: printable ASCII keys, skipped while Ctrl/Alt are held (shortcuts)
             local v = input.KeyCode.Value
             if v >= 32 and v < 127 and not (ctrl or alt) then
                 local c = string.char(v)
                 if shift then c = SHIFTED[c] or c:upper() end
-                io:AddInputCharacter(string.byte(c))
+                -- While the proxy may own text input, hold the char: NewFrame uses the proxy's text if it changed
+                -- (correct layout/unicode), otherwise these. So typing works even if the proxy silently lost focus.
+                if proxy_focused then table.insert(ImGui_ImplRoblox_GetBackendData().PendingChars, string.byte(c))
+                else io:AddInputCharacter(string.byte(c)) end
             end
         end
     end)
@@ -34314,6 +34319,34 @@ function ImGui_ImplRoblox_Init(parent, render_scale)
         end
     end)
 
+    -- Text proxy: a hidden TextBox holds focus while an imgui text field is active, so the OS gives us typing (any
+    -- layout/unicode), paste (Ctrl+V) and copy/cut (Ctrl+C/X of the proxy's text = imgui's current selection).
+    local proxy = Instance.new("TextBox")
+    proxy.Name = "TextProxy"
+    proxy.BackgroundTransparency = 1
+    proxy.TextTransparency = 0 -- kept opaque but parked off screen: a transparent TextBox may not get native paste
+    proxy.BorderSizePixel = 0
+    proxy.Size = UDim2.fromOffset(200, 20)
+    proxy.Position = UDim2.fromOffset(-10000, -10000)
+    proxy.MultiLine = true
+    proxy.ClearTextOnFocus = false
+    proxy.TextEditable = true
+    proxy.Text = ""
+    proxy.Parent = gui
+    bd.Proxy, bd.ProxyText, bd.PendingChars = proxy, "", {}
+    -- Clicking elsewhere (or Roblox taking focus) ends the edit, like clicking outside the field in imgui.
+    -- (Text is polled in NewFrame instead of using Text changed signals: those are deferred in Roblox.)
+    connect(proxy.FocusLost, function()
+        if bd.ProxyDebug then print("[ImGui text proxy] FocusLost, mouse over imgui:", ImGui.GetIO().WantCaptureMouse) end
+        if bd.ProxyReleasing then return end
+        -- Roblox drops TextBox focus on any click, including clicks inside imgui (e.g. moving the cursor within the
+        -- same field). Those must not end the edit: just recapture next frame. Only a click outside imgui ends it.
+        if ImGui.GetIO().WantCaptureMouse then bd.ProxyLostId = nil; return end
+        bd.ProxyLostId = bd.ProxyActiveId -- don't recapture for the same field
+        local g = ImGui.GetCurrentContext()
+        if g and g.ActiveId ~= 0 and g.ActiveId == bd.ProxyActiveId then ImGui.ClearActiveID() end
+    end)
+
     connect(UserInputService.WindowFocused, function() ImGui.GetIO():AddFocusEvent(true) end)
     connect(UserInputService.WindowFocusReleased, function() ImGui.GetIO():AddFocusEvent(false) end)
 end
@@ -34356,6 +34389,86 @@ function ImGui_ImplRoblox_NewFrame()
         io:AddMousePosEvent(m.X * bd.Scale, m.Y * bd.Scale)
     end
 
+    -- Text proxy: focused while an imgui text field is active. proxy_focused only when Roblox really gave it focus,
+    -- otherwise the KeyCode fallback keeps typing working.
+    local proxy = bd.Proxy
+    local g = ImGui.GetCurrentContext()
+    local focused_box = UserInputService:GetFocusedTextBox()
+    if io.WantTextInput and g.ActiveId ~= 0 then
+        if g.ActiveId ~= bd.ProxyActiveId or g.ActiveIdIsJustActivated or g.IO.MouseClicked[0] then bd.ProxyActiveId = g.ActiveId; bd.ProxyLostId = nil end -- (re)clicking a field recaptures
+        local mouse_up = not (io.MouseDown[0] or io.MouseDown[1] or io.MouseDown[2])
+        if focused_box ~= proxy and mouse_up and bd.ProxyLostId ~= g.ActiveId and (focused_box == nil or not focused_box:IsDescendantOf(game)) then
+            bd.ProxyText = proxy.Text -- what it already holds is not new input (else re-typing it would collapse imgui's selection)
+            proxy:CaptureFocus()
+            focused_box = UserInputService:GetFocusedTextBox()
+            if bd.ProxyDebug then print("[ImGui text proxy] CaptureFocus ->", focused_box == proxy and "focused" or ("FAILED, focused = " .. tostring(focused_box))) end
+        end
+    elseif focused_box == proxy then
+        bd.ProxyReleasing = true
+        proxy:ReleaseFocus()
+        bd.ProxyReleasing = false
+        focused_box = nil
+    end
+    local was_focused = proxy_focused
+    proxy_focused = focused_box == proxy
+    local used_proxy_text = false
+    if proxy_focused then
+        -- 1) whatever the OS put in the proxy since last frame (typing, paste, cut) replaces imgui's selection
+        local text = proxy.Text
+        if text ~= bd.ProxyText and bd.ProxyDebug then print("[ImGui text proxy] text", string.format("%q", text), "was", string.format("%q", tostring(bd.ProxyText))) end
+        if text ~= bd.ProxyText and text ~= bd.ProxyLastRaw then -- (LastRaw: don't re-send if our reset hasn't applied yet)
+            bd.ProxyLastRaw = text
+            -- InputText ignores characters while Ctrl is held (upstream, so shortcuts don't type); a paste arrives with
+            -- Ctrl still down, so release Ctrl around the characters in the event queue.
+            local ctrl = io.KeyCtrl or UserInputService:IsKeyDown(Enum.KeyCode.LeftControl) or UserInputService:IsKeyDown(Enum.KeyCode.RightControl)
+            if ctrl then io:AddKeyEvent(ImGuiMod_Ctrl, false) end
+            local prev = bd.ProxyText or ""
+            if #text < #prev and prev:sub(1, #text) == text and text:sub(-1) ~= "\n" then
+                -- The TextBox deleted from its own text (Backspace/Delete; Roblox can't hold a real selection in it, so it
+                -- may remove just 1 char). Apply the deletion with imgui's own selection instead: one Backspace deletes
+                -- the whole imgui selection, or one char if none. Skipped if imgui already got the key event.
+                if not bd.DeleteKeySeen then io:AddKeyEvent(ImGuiKey.Backspace, true); io:AddKeyEvent(ImGuiKey.Backspace, false) end
+            elseif text ~= "\n" and text ~= "\r" and text ~= "\t" then -- Enter/Tab arrive as key events
+                local prev = bd.ProxyText or ""
+                if #text > 0 and (prev == "" or text:sub(1, #prev) ~= prev or #text <= #prev) then
+                    for _, cp in utf8.codes(text) do io:AddInputCharacter(cp) end
+                elseif #text > #prev then
+                    for _, cp in utf8.codes(text:sub(#prev + 1)) do io:AddInputCharacter(cp) end
+                end
+            end
+            if ctrl then io:AddKeyEvent(ImGuiMod_Ctrl, true) end
+            used_proxy_text = true
+            bd.ProxyText = nil
+        end
+        -- 2) mirror imgui's selection, fully selected, so the native Ctrl+C / Ctrl+X copy exactly that
+        local st = g.InputTextState
+        local sel = ""
+        if st and st.ID ~= 0 and st.ID == g.ActiveId and st.Stb and st:HasSelection() then
+            local a, b = math.min(st.Stb.select_start, st.Stb.select_end), math.max(st.Stb.select_start, st.Stb.select_end)
+            sel = ImGui._ByteArrayToString(st.TextA.Data, a, b) -- stb positions are 1-based in this port
+        end
+        if sel ~= bd.ProxyText then
+            proxy.Text = sel
+            bd.ProxyLastRaw = nil
+            bd.ProxyText = sel
+            if bd.ProxyDebug then print("[ImGui text proxy] mirror selection", string.format("%q", sel)) end
+        end
+        -- keep imgui's selection fully selected in the proxy, so Ctrl+C copies it and typing/Ctrl+V replaces it
+        local want_sel, want_cur = (#sel > 0) and 1 or -1, #sel + 1
+        if proxy.SelectionStart ~= want_sel then proxy.SelectionStart = want_sel end
+        if proxy.CursorPosition ~= want_cur then proxy.CursorPosition = want_cur end
+    end
+
+    bd.DeleteKeySeen = false
+
+    -- Held KeyCode chars: dropped if the proxy delivered the text, otherwise typed (proxy didn't really get the keys)
+    local pending = bd.PendingChars
+    if #pending > 0 then
+        if not used_proxy_text then for _, c in ipairs(pending) do io:AddInputCharacter(c) end end
+        table.clear(pending)
+    end
+    if bd.ProxyDebug and was_focused ~= proxy_focused then print("[ImGui text proxy] proxy_focused =", proxy_focused) end
+
     -- While the mouse is over imgui, make the tiles Active so Roblox stops passing clicks/wheel to the game (camera zoom etc.)
     local want = io.WantCaptureMouse
     if want ~= bd.TilesActive then
@@ -34396,6 +34509,7 @@ ImGui_ImplRoblox = {
     SetRenderScale = ImGui_ImplRoblox_SetRenderScale,
     SetRenderRate  = ImGui_ImplRoblox_SetRenderRate,
     SetOverlay     = ImGui_ImplRoblox_SetOverlay,
+    SetTextProxyDebug = function(on) ImGui_ImplRoblox_GetBackendData().ProxyDebug = on end, -- prints focus/text events
     CreateTexture  = ImGui_ImplRoblox_CreateTexture,
     DestroyTexture = ImGui_ImplRoblox_DestroyTexture,
     GetRenderScale = function() return ImGui_ImplRoblox_GetBackendData().Scale end,
diff --git a/tools/test/roblox_mock.luau b/tools/test/roblox_mock.luau
index 5f748f7..9388299 100644
--- a/tools/test/roblox_mock.luau
+++ b/tools/test/roblox_mock.luau
@@ -60,6 +60,7 @@ local InstMethods = {}
 local InstMT = {}
 InstMT.__index = function(t, k)
     if k == "Parent" then return rawget(t, "_parent") end
+    local pv = rawget(t, "_props")[k]; if pv ~= nil then return pv end
     local m = InstMethods[k]; if m then return m end
     for _, c in ipairs(rawget(t, "_children")) do if c.Name == k then return c end end
     return nil
@@ -71,13 +72,18 @@ InstMT.__newindex = function(t, k, v)
         rawset(t, "_parent", v)
         if v then table.insert(rawget(v, "_children"), t) end
     else
-        rawset(t, k, v)
+        local props = rawget(t, "_props")
+        local old = props[k]
+        props[k] = v
+        local sigs = rawget(t, "_propsigs")
+        if sigs and sigs[k] and old ~= v then sigs[k]:Fire() end
     end
 end
 local function newInst(class, name, parent)
-    local o = setmetatable({ ClassName = class, Name = name or class, _children = {} }, InstMT)
+    local o = setmetatable({ _children = {}, _props = { ClassName = class, Name = name or class } }, InstMT)
     if class == "ScreenGui" or class == "Frame" or class == "ImageLabel" then o.AbsoluteSize = v2(SCREEN_W, SCREEN_H) end
     o.Visible = true
+    if class == "TextBox" then rawget(o, "_props").FocusLost = Signal() end
     if class == "BindableEvent" then local sig = Signal(); rawset(o, "Event", sig); rawset(o, "Fire", function(_, ...) sig:Fire(...) end) end
     if parent then o.Parent = parent end
     return o
@@ -95,6 +101,14 @@ function InstMethods:IsA(class)
     return self.ClassName == class
 end
 function InstMethods:Destroy() self.Parent = nil end
+local focused_box = nil
+function InstMethods:GetPropertyChangedSignal(prop)
+    local sigs = rawget(self, "_propsigs") or {}; rawset(self, "_propsigs", sigs)
+    sigs[prop] = sigs[prop] or Signal(); return sigs[prop]
+end
+function InstMethods:CaptureFocus() focused_box = self end
+function InstMethods:_loseFocus() if focused_box == self then focused_box = nil; local fl = rawget(self, "_props").FocusLost; if fl then fl:Fire(false) end end end
+function InstMethods:ReleaseFocus() self:_loseFocus() end
 
 -- Services
 local mouse = v2(0, 0)
@@ -103,6 +117,7 @@ local UIS = {
     InputBegan = Signal(), InputEnded = Signal(), InputChanged = Signal(), WindowFocused = Signal(), WindowFocusReleased = Signal(),
 }
 function UIS:GetMouseLocation() return mouse end
+function UIS:GetFocusedTextBox() return focused_box end
 function UIS:IsKeyDown(kc) return keys_down[kc] == true end
 
 local RunService = { Heartbeat = Signal(), Stepped = Signal(), PreAnimation = Signal(), RenderStepped = Signal() }
diff --git a/tools/test/scripts/t_textproxy.luau b/tools/test/scripts/t_textproxy.luau
new file mode 100644
index 0000000..4d2936d
--- /dev/null
+++ b/tools/test/scripts/t_textproxy.luau
@@ -0,0 +1,73 @@
+-- Text proxy: typing/paste arrive through the hidden TextBox, and its text mirrors the InputText selection (for copy).
+local G = require(game:GetService("ReplicatedStorage"):WaitForChild("ImGui"))
+local ImGui, ImVec2 = G.ImGui, G.ImVec2
+local UIS = game:GetService("UserInputService")
+ImGui.CreateContext(); G.ImGui_ImplRoblox.Init()
+local io = ImGui.GetIO()
+local buf = ImGui.NewTextBuffer("", 64)
+local proxy
+local f = 0
+game:GetService("RunService").Stepped:Connect(function()
+    f += 1
+    G.ImGui_ImplRoblox.NewFrame()
+    proxy = proxy or game:GetService("Players").LocalPlayer.PlayerGui.ImGui.TextProxy
+    if f == 3 then io:AddMousePosEvent(60, 45); io:AddMouseButtonEvent(0, true) end
+    if f == 4 then io:AddMouseButtonEvent(0, false) end
+    if f == 8 then assert(UIS:GetFocusedTextBox() == proxy, "proxy focused"); proxy.Text = "abc" end            -- typed
+    if f == 10 then io:AddKeyEvent(G.ImGuiMod_Ctrl, true); proxy.Text = "hello world" end -- pasted with Ctrl held
+    if f == 11 then io:AddKeyEvent(G.ImGuiMod_Ctrl, false) end                                                             -- pasted
+    if f == 13 then io:AddKeyEvent(G.ImGuiMod_Ctrl, true); io:AddKeyEvent(G.ImGuiKey.A, true) end             -- select all
+    if f == 14 then io:AddKeyEvent(G.ImGuiKey.A, false); io:AddKeyEvent(G.ImGuiMod_Ctrl, false) end
+    ImGui.NewFrame()
+    ImGui.SetNextWindowPos(ImVec2(10, 10)); ImGui.SetNextWindowSize(ImVec2(300, 100))
+    ImGui.Begin("T"); ImGui.InputText("##t", buf, 64); ImGui.End()
+    ImGui.Render(); G.ImGui_ImplRoblox.RenderDrawData(ImGui.GetDrawData())
+    if f == 12 then local st = ImGui.GetCurrentContext().InputTextState  -- (buf itself is written on validation/deactivation)
+        local got = G.ImGui._ByteArrayToString(st.TextA.Data, 1, st.TextLen + 1)
+        assert(got == "abchello world", "text: " .. got) end
+    if f == 15 then proxy:_loseFocus() end
+    -- keys while the proxy reports focus but receives nothing (Roblox silently not delivering): must still type
+    if f == 20 then
+        io:AddMousePosEvent(60, 45); io:AddMouseButtonEvent(0, true)
+    end
+    if f == 21 then io:AddMouseButtonEvent(0, false) end
+    if f == 24 then
+        assert(UIS:GetFocusedTextBox() == proxy, "proxy focused again")
+        local k = { UserInputType = Enum.UserInputType.Keyboard, KeyCode = Enum.KeyCode.Z, Position = { X = 0, Y = 0, Z = 0 } }
+        UIS.InputBegan:Fire(k, true); UIS.InputEnded:Fire(k, true)
+    end -- click inside imgui (mouse is over the field): edit must survive
+    if f == 16 then
+        assert(ImGui.GetCurrentContext().ActiveId ~= 0, "edit ended by a click inside imgui")
+        assert(UIS:GetFocusedTextBox() == proxy, "proxy not recaptured")
+        assert(proxy.Text == "abchello world", "selection mirror: " .. tostring(proxy.Text))
+        io:AddMousePosEvent(900, 900) -- move off imgui, then the user clicks into the game
+    end
+    if f == 17 then proxy:_loseFocus() end
+    if f == 19 then
+        assert(ImGui.GetCurrentContext().ActiveId == 0, "field still active after focus lost")
+        assert(UIS:GetFocusedTextBox() == nil, "proxy recaptured")
+        assert(ImGui.TextBufferToString(buf) == "abchello world", "buf: " .. ImGui.TextBufferToString(buf))
+    end
+    -- click inside the field with a selection (Roblox drops focus on press, we recapture on release): selection must survive
+    if f == 28 then io:AddKeyEvent(G.ImGuiMod_Ctrl, true); io:AddKeyEvent(G.ImGuiKey.A, true) end
+    if f == 29 then io:AddKeyEvent(G.ImGuiKey.A, false); io:AddKeyEvent(G.ImGuiMod_Ctrl, false) end
+    if f == 31 then proxy:_loseFocus() end
+    if f == 34 then
+        local st = ImGui.GetCurrentContext().InputTextState
+        assert(st:HasSelection(), "selection lost after refocus")
+        assert(#proxy.Text > 5 and proxy.Text == G.ImGui._ByteArrayToString(st.TextA.Data, 1, st.TextLen + 1), "mirror after refocus: " .. proxy.Text)
+        print("REFOCUS OK")
+        proxy.Text = proxy.Text:sub(1, -2) -- Roblox Backspace without a real TextBox selection: removes 1 char
+    end
+    if f == 37 then
+        local st = ImGui.GetCurrentContext().InputTextState
+        assert(st.TextLen == 0, "backspace should delete imgui's whole selection, len " .. st.TextLen)
+        print("BACKSPACE OK")
+    end
+    if f == 27 then
+        local st = ImGui.GetCurrentContext().InputTextState
+        local got = G.ImGui._ByteArrayToString(st.TextA.Data, 1, st.TextLen + 1)
+        assert(got:find("z"), "key fallback while proxy focused: " .. got)
+        print("PROXY OK")
+    end
+end)