diff --git a/js/dos/ext/vis/docs/js/prettify/lang-yaml.js b/js/dos/ext/vis/docs/js/prettify/lang-yaml.js
new file mode 100644
index 0000000..f2f3607
--- /dev/null
+++ b/js/dos/ext/vis/docs/js/prettify/lang-yaml.js
@@ -0,0 +1,2 @@
+PR.registerLangHandler(PR.createSimpleLexer([["pun",/^[:|>?]+/,null,":|>?"],["dec",/^%(?:YAML|TAG)[^#\r\n]+/,null,"%"],["typ",/^[&]\S+/,null,"&"],["typ",/^!\S*/,null,"!"],["str",/^"(?:[^\\"]|\\.)*(?:"|$)/,null,'"'],["str",/^'(?:[^']|'')*(?:'|$)/,null,"'"],["com",/^#[^\r\n]*/,null,"#"],["pln",/^\s+/,null," \t\r\n"]],[["dec",/^(?:---|\.\.\.)(?:[\r\n]|$)/],["pun",/^-/],["kwd",/^\w+:[ \r\n]/],["pln",/^\w+/]]),
+["yaml","yml"])
\ No newline at end of file