diff --git a/runtime/ftplugin/cpp.vim b/runtime/ftplugin/cpp.vim
index fc92935..fac3edd 100644
--- a/runtime/ftplugin/cpp.vim
+++ b/runtime/ftplugin/cpp.vim
@@ -1,7 +1,7 @@
 " Vim filetype plugin file
 " Language:	C++
 " Maintainer:	The Vim Project <https://github.com/vim/vim>
-" Last Change:	2023 Aug 10
+" Last Change:	2024 Jun 06
 " Former Maintainer:	Bram Moolenaar <Bram@vim.org>
 
 " Only do this when not done yet for this buffer
@@ -12,6 +12,10 @@
 " Behaves mostly just like C
 runtime! ftplugin/c.vim ftplugin/c_*.vim ftplugin/c/*.vim
 
+" Change 'commentstring' to "C++ style"/"mono-line" comments
+setlocal commentstring=//\ %s
+let b:undo_ftplugin ..= ' | setl commentstring<'
+
 " C++ uses templates with <things>
 " Disabled, because it gives an error for typing an unmatched ">".
 " set matchpairs+=<:>