diff --git a/package.json b/package.json
index 692e241..0a23cb3 100644
--- a/package.json
+++ b/package.json
@@ -3,7 +3,7 @@
   "version": "0.8.1",
   "scripts": {
     "tdd:unit": "mocha --watch --timeout 5000 test/unit/",
-    "clear-html-cache": "rm test/tools/fetch-cache -r",
+    "clear-html-cache": "rm -rf test/tools/fetch-cache",
     "firefox": "web-ext -s src run",
     "coverage": "nyc --reporter=lcov mocha -R=progress --forbid-only test/unit/ && open coverage/lcov-report/index.html",
     "lint:eslint": "eslint --ignore-path .gitignore .",