diff --git a/types/fullpage.js/tsconfig.json b/types/fullpage.js/tsconfig.json
index 6fbc085728..d20953732c 100644
--- a/types/fullpage.js/tsconfig.json
+++ b/types/fullpage.js/tsconfig.json
@@ -8,6 +8,7 @@
         "noImplicitAny": true,
         "noImplicitThis": true,
         "strictNullChecks": false,
+        "strictFunctionTypes": true,
         "baseUrl": "../",
         "typeRoots": [
             "../"