diff --git a/runtime/filetype.vim b/runtime/filetype.vim
index bd1d2e9..c3d370d 100644
--- a/runtime/filetype.vim
+++ b/runtime/filetype.vim
@@ -1750,6 +1750,7 @@
 
 " Microsoft Visual Studio Solution
 au BufNewFile,BufRead *.sln			setf solution
+au BufNewFile,BufRead *.slnf			setf json
 
 " Spice
 au BufNewFile,BufRead *.sp,*.spice		setf spice
diff --git a/src/testdir/test_filetype.vim b/src/testdir/test_filetype.vim
index 719d690..8fb7d92 100644
--- a/src/testdir/test_filetype.vim
+++ b/src/testdir/test_filetype.vim
@@ -263,7 +263,7 @@
     \ 'jgraph': ['file.jgr'],
     \ 'jovial': ['file.jov', 'file.j73', 'file.jovial'],
     \ 'jproperties': ['file.properties', 'file.properties_xx', 'file.properties_xx_xx', 'some.properties_xx_xx_file'],
-    \ 'json': ['file.json', 'file.jsonp', 'file.json-patch', 'file.webmanifest', 'Pipfile.lock', 'file.ipynb', '.babelrc', '.eslintrc', '.prettierrc', '.firebaserc'],
+    \ 'json': ['file.json', 'file.jsonp', 'file.json-patch', 'file.webmanifest', 'Pipfile.lock', 'file.ipynb', '.babelrc', '.eslintrc', '.prettierrc', '.firebaserc', 'file.slnf'],
     \ 'jsonc': ['file.jsonc'],
     \ 'jsp': ['file.jsp'],
     \ 'julia': ['file.jl'],
diff --git a/src/version.c b/src/version.c
index 20c78d7..6b4708d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -750,6 +750,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3880,
+/**/
     3879,
 /**/
     3878,