diff --git a/runtime/filetype.vim b/runtime/filetype.vim
index 9b18b1b..247e873 100644
--- a/runtime/filetype.vim
+++ b/runtime/filetype.vim
@@ -2305,6 +2305,9 @@
 " csh scripts ending in a star
 au BufNewFile,BufRead .login*,.cshrc*  call dist#ft#CSH()
 
+" tmux configuration with arbitrary extension
+au BufNewFile,BufRead {.,}tmux*.conf*		setf tmux
+
 " VHDL
 au BufNewFile,BufRead *.vhdl_[0-9]*		call s:StarSetf('vhdl')
 
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 0a55ca6..557cf5e 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -504,7 +504,7 @@
     \ 'tidy': ['.tidyrc', 'tidyrc', 'tidy.conf'],
     \ 'tilde': ['file.t.html'],
     \ 'tli': ['file.tli'],
-    \ 'tmux': ['tmuxfile.conf', '.tmuxfile.conf', '.tmux-file.conf', '.tmux.conf', 'tmux-file.conf', 'tmux.conf'],
+    \ 'tmux': ['tmuxfile.conf', '.tmuxfile.conf', '.tmux-file.conf', '.tmux.conf', 'tmux-file.conf', 'tmux.conf', 'tmux.conf.local'],
     \ 'toml': ['file.toml'],
     \ 'tpp': ['file.tpp'],
     \ 'treetop': ['file.treetop'],
diff --git a/src/version.c b/src/version.c
index e09abfa..1f292bb 100644
--- a/src/version.c
+++ b/src/version.c
@@ -758,6 +758,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3501,
+/**/
     3500,
 /**/
     3499,