diff --git a/packages/tailwindcss-language-server/src/util/html.ts b/packages/tailwindcss-language-server/src/util/html.ts
index 5458641..f9e687c 100644
--- a/packages/tailwindcss-language-server/src/util/html.ts
+++ b/packages/tailwindcss-language-server/src/util/html.ts
@@ -16,6 +16,7 @@ export const HTML_LANGUAGES = [
   'leaf',
   'liquid',
   'markdown',
+  'mustache',
   'njk',
   'nunjucks',
   'php',
diff --git a/packages/tailwindcss-vscode/src/lib/languages.ts b/packages/tailwindcss-vscode/src/lib/languages.ts
index 688ff78..b20674a 100644
--- a/packages/tailwindcss-vscode/src/lib/languages.ts
+++ b/packages/tailwindcss-vscode/src/lib/languages.ts
@@ -15,6 +15,7 @@ export const LANGUAGES = [
   'leaf',
   'liquid',
   'markdown',
+  'mustache',
   'njk',
   'nunjucks',
   'php',