diff --git a/doc/changes/8.2.rst b/doc/changes/8.2.rst
index 31e218c5e20..4e9d2c8bada 100644
--- a/doc/changes/8.2.rst
+++ b/doc/changes/8.2.rst
@@ -3,7 +3,18 @@ Sphinx 8.2
 ==========
 
 
-Release 8.2.2 (released Mar 01, 2025)
+Release 8.2.3 (released Mar 02, 2025)
+=====================================
+
+Bugs fixed
+----------
+
+* #13403: Define ``_StrPath.__radd__()``.
+  Patch by Adam Turner.
+* #13399: Fix _CurrentDocument membership testing with '{c,cpp}:parent_symbol'.
+  Patch by Adam Turner.
+
+Release 8.2.2 (released Mar 02, 2025)
 =====================================
 
 Bugs fixed
@@ -11,9 +22,11 @@ Bugs fixed
 
 * #13392: Fix argument type for ``jieba.load_userdict()``.
 * Add workaround for ``nbsphinx`` implicit imports.
+  Patch by Adam Turner.
 * #13402: Ensure inline ``<script/>`` tags are written exactly once.
+  Patch by Dmitry Shachnev and Adam Turner.
 * #13391: apidoc: Fix TOC file not having a title.
-  Patch by Dave Hoese.
+  Patch by Dave Hoese and Adam Turner.
 
 Release 8.2.1 (released Feb 21, 2025)
 =====================================
diff --git a/sphinx/__init__.py b/sphinx/__init__.py
index d8287d4ea19..35da74e775d 100644
--- a/sphinx/__init__.py
+++ b/sphinx/__init__.py
@@ -17,7 +17,7 @@
 if TYPE_CHECKING:
     from typing import Final
 
-__version__: Final = '8.2.2'
+__version__: Final = '8.2.3'
 __display_version__: Final = __version__  # used for command line version
 
 warnings.filterwarnings(
@@ -35,7 +35,7 @@
 #:
 #: .. versionadded:: 1.2
 #:    Before version 1.2, check the string ``sphinx.__version__``.
-version_info: Final = (8, 2, 2, 'final', 0)
+version_info: Final = (8, 2, 3, 'final', 0)
 
 package_dir: Final = _StrPath(__file__).resolve().parent
 
diff --git a/sphinx/environment/__init__.py b/sphinx/environment/__init__.py
index 2e4bc230cc1..79fa6278549 100644
--- a/sphinx/environment/__init__.py
+++ b/sphinx/environment/__init__.py
@@ -1069,7 +1069,7 @@ def __delitem__(self, key: str) -> None:
 
     def __contains__(self, item: str) -> bool:
         if item in {'c:parent_symbol', 'cpp:parent_symbol'}:
-            return getattr(self, item) is not None
+            return getattr(self, self.__attr_map[item]) is not None
         return item in self.__attr_map or item in self._extension_data
 
     def __iter__(self) -> Iterator[str]:
diff --git a/sphinx/util/_pathlib.py b/sphinx/util/_pathlib.py
index a304ff75ca4..0506131f962 100644
--- a/sphinx/util/_pathlib.py
+++ b/sphinx/util/_pathlib.py
@@ -57,6 +57,10 @@ def __add__(self, other: str) -> str:
             warnings.warn(_MSG, RemovedInSphinx90Warning, stacklevel=2)
             return self.__str__() + other
 
+        def __radd__(self, other: str) -> str:
+            warnings.warn(_MSG, RemovedInSphinx90Warning, stacklevel=2)
+            return other + self.__str__()
+
         def __bool__(self) -> bool:
             if not self.__str__():
                 warnings.warn(_MSG, RemovedInSphinx90Warning, stacklevel=2)
@@ -108,6 +112,10 @@ def __add__(self, other: str) -> str:
             warnings.warn(_MSG, RemovedInSphinx90Warning, stacklevel=2)
             return self.__str__() + other
 
+        def __radd__(self, other: str) -> str:
+            warnings.warn(_MSG, RemovedInSphinx90Warning, stacklevel=2)
+            return other + self.__str__()
+
         def __bool__(self) -> bool:
             if not self.__str__():
                 warnings.warn(_MSG, RemovedInSphinx90Warning, stacklevel=2)