diff --git a/Misc/NEWS b/Misc/NEWS
index ae4c06b..a76b995 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -600,6 +600,8 @@
 Build
 -----
 
+- Issue #10055: Make json C89-compliant in UCS4 mode.
+
 - Issue #6244: Allow detect_tkinter to look for Tcl/Tk 8.6.
 
 - Issue #1633863: Don't ignore $CC under AIX.