diff --git a/runtime/doc/version9.txt b/runtime/doc/version9.txt
index e2bc66be04..c5ed3da001 100644
--- a/runtime/doc/version9.txt
+++ b/runtime/doc/version9.txt
@@ -1,4 +1,4 @@
-*version9.txt*	For Vim version 9.1.  Last change: 2026 Feb 07
+*version9.txt*	For Vim version 9.1.  Last change: 2026 Feb 08
 
 
 		  VIM REFERENCE MANUAL	  by Bram Moolenaar
@@ -52528,4 +52528,8 @@ Problem:  tests: Test_wayland_protocol_error_overflow() fails
           (after v9.1.2139)
 Solution: try/catch the expected error
 
+Patch 9.1.2141
+Problem:  Truncation when serializing libsodium encryption parameters.
+Solution: Correctly cast to long long type (Yasuhiro Matsumoto).
+
  vim:tw=78:ts=8:noet:ft=help:norl:fdm=manual:nofoldenable
diff --git a/src/crypt.c b/src/crypt.c
index da1022644d..794594f910 100644
--- a/src/crypt.c
+++ b/src/crypt.c
@@ -1356,7 +1356,7 @@ crypt_long_long_to_char(long long n, char_u *s)
     for (i = 0; i < 8; i++)
     {
 	s[i] = (char_u)(n & 0xff);
-	n = (unsigned)n >> 8;
+	n = (unsigned long long)n >> 8;
     }
 }
 
@@ -1367,7 +1367,7 @@ crypt_int_to_char(int n, char_u *s)
     for (i = 0; i < 4; i++)
     {
 	s[i] = (char_u)(n & 0xff);
-	n = (unsigned)n >> 8;
+	n = (unsigned long long)n >> 8;
     }
 }
 
diff --git a/src/version.c b/src/version.c
index e6b867cf6d..5f437f42d6 100644
--- a/src/version.c
+++ b/src/version.c
@@ -734,6 +734,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2141,
 /**/
     2140,
 /**/