diff --git a/docs/modernization/debt.md b/docs/modernization/debt.md
index 52a5693..db3798e 100644
--- a/docs/modernization/debt.md
+++ b/docs/modernization/debt.md
@@ -61,6 +61,12 @@ agent or engineer to remove them without reconstructing context from chat.
 - 2026-06-13: `PLT-006` was narrowed again. macOS cursor visibility now routes
   through the Apple service boundary instead of the catch-all legacy adapter;
   the Apple path still owns the OS-specific cursor toggle.
+- 2026-06-13: `PLT-007` was narrowed again. macOS UI-state saving now routes
+  through the Apple service boundary instead of the catch-all legacy adapter;
+  the Apple path still owns the OS-specific UI-state save call.
+- 2026-06-13: `PLT-007` was narrowed again. macOS UI-state saving now routes
+  through `src/platform_apple/apple_platform_services.*` instead of the
+  catch-all legacy adapter; the Apple path still owns the OS-specific save call.
 - 2026-06-13: `DEBT-0036` was narrowed again. `NodeStrokePreview::draw_stroke_immediate()`
   now routes final composite execution and preview copy-back through a retained
   local wrapper, leaving the call site with only sequence wiring.
diff --git a/docs/modernization/tasks.md b/docs/modernization/tasks.md
index 97a268b..2b1e026 100644
--- a/docs/modernization/tasks.md
+++ b/docs/modernization/tasks.md
@@ -1362,6 +1362,40 @@ Completed Task Log:
 | --- | --- | ---: | --- | --- |
 | 2026-06-13 | PLT-006 | +1 platform alignment and package parity | `ctest --preset desktop-fast --build-config Debug -R pp_platform_api_tests --output-on-failure`; `cmake --build --preset windows-msvc-default --config Debug --target pp_platform_api_tests` | `fc4f5e40` |
 
+### PLT-007 - Split Mac UI State Saving From Legacy Platform Adapter
+
+Status: Done
+Score: +1 platform alignment and package parity
+Debt: `DEBT-0017`, `DEBT-0052`
+Scope: `src/platform_legacy/legacy_platform_services.cpp`,
+`src/platform_apple/apple_platform_services.*`
+
+Goal:
+
+Move macOS UI-state saving out of the catch-all legacy platform adapter into
+the Apple platform service boundary. Preserve current macOS UI-state saving
+behavior and keep non-macOS behavior unchanged.
+
+Done Checks:
+
+- `src/platform_legacy/legacy_platform_services.cpp` no longer owns the macOS
+  UI-state save branch.
+- macOS UI-state saving still dispatches through the Apple service path.
+- The debt log records the reduced macOS platform tail.
+
+Validation:
+
+```powershell
+ctest --preset desktop-fast --build-config Debug -R pp_platform_api_tests --output-on-failure
+cmake --build --preset windows-msvc-default --config Debug --target pp_platform_api_tests
+```
+
+Completed Task Log:
+
+| Date | Task | Score | Validation | Commit |
+| --- | --- | ---: | --- | --- |
+| 2026-06-13 | PLT-007 | +1 platform alignment and package parity | `ctest --preset desktop-fast --build-config Debug -R pp_platform_api_tests --output-on-failure`; `cmake --build --preset windows-msvc-default --config Debug --target pp_platform_api_tests` | `pending` |
+
 ### STR-010 - Extract Remaining Draw Merge Composite Orchestration
 
 Status: Done
diff --git a/src/platform_apple/apple_platform_services.cpp b/src/platform_apple/apple_platform_services.cpp
index 157978c..0244c5c 100644
--- a/src/platform_apple/apple_platform_services.cpp
+++ b/src/platform_apple/apple_platform_services.cpp
@@ -169,4 +169,11 @@ void AppleDocumentPlatformServices::set_cursor_visible(bool visible) const
 #endif
 }
 
+void AppleDocumentPlatformServices::save_ui_state() const
+{
+#if defined(__OSX__)
+    [App::I->osx_app save_ui_state];
+#endif
+}
+
 }
diff --git a/src/platform_apple/apple_platform_services.h b/src/platform_apple/apple_platform_services.h
index bcde797..d238b66 100644
--- a/src/platform_apple/apple_platform_services.h
+++ b/src/platform_apple/apple_platform_services.h
@@ -38,6 +38,7 @@ public:
     void display_file(std::string_view path) const;
     void share_file(std::string_view path) const;
     void set_cursor_visible(bool visible) const;
+    void save_ui_state() const;
 
 private:
     PlatformFamily family_;
diff --git a/src/platform_legacy/legacy_platform_services.cpp b/src/platform_legacy/legacy_platform_services.cpp
index b4899bd..2f54764 100644
--- a/src/platform_legacy/legacy_platform_services.cpp
+++ b/src/platform_legacy/legacy_platform_services.cpp
@@ -451,9 +451,7 @@ public:
     {
         if (!pp::platform::platform_saves_native_ui_state(pp::platform::current_platform_family()))
             return;
-#ifdef __OSX__
-        [App::I->osx_app save_ui_state];
-#endif
+        active_apple_document_platform_services().save_ui_state();
     }
 
     [[nodiscard]] bool enables_live_asset_reloading() override