diff --git a/CHANGES b/CHANGES
index a105fa084..029b9efcb 100644
--- a/CHANGES
+++ b/CHANGES
@@ -28,6 +28,7 @@ Bugs fixed
 * #4716: Generation PDF file with TexLive on Windows, file not found error
 * #4574: vertical space before equation in latex
 * #4720: message when an image is mismatched for builder is not clear
+* #4655, #4684: Incomplete localization strings in Polish and Chinese
 
 Testing
 --------
diff --git a/sphinx/locale/zh_CN/LC_MESSAGES/sphinx.po b/sphinx/locale/zh_CN/LC_MESSAGES/sphinx.po
index 06f19e6f7..bf7bbb7b9 100644
--- a/sphinx/locale/zh_CN/LC_MESSAGES/sphinx.po
+++ b/sphinx/locale/zh_CN/LC_MESSAGES/sphinx.po
@@ -265,7 +265,7 @@ msgstr ""
 msgid ""
 "the extension %r was already merged with Sphinx since version %s; this "
 "extension is ignored."
-msgstr "自版本 %s 开始，扩展 %r 已合并至 Sphinx；该扩展被忽略。"
+msgstr ""
 
 #: sphinx/registry.py:315
 msgid "Original exception:\n"