diff --git a/package.json b/package.json
index d96b13e3cc5..fb7a9492936 100644
--- a/package.json
+++ b/package.json
@@ -130,7 +130,7 @@
     "test": "node --max_old_space_size=4096 node_modules/@ckeditor/ckeditor5-dev-tests/bin/test.js",
     "manual": "node --max_old_space_size=4096 node_modules/@ckeditor/ckeditor5-dev-tests/bin/test-manual.js",
     "bootstrap": "yarn install",
-    "clean": "rm -rf node_modules",
+    "clean": "rm -rf ./node_modules && rm -rf ./external/*/node_modules",
     "reset": "rm -rf ./node_modules && yarn run bootstrap",
     "reinstall": "yarn run clean && yarn run bootstrap",
     "docs": "node --max-old-space-size=4096 ./scripts/docs/build-docs.js",
@@ -167,6 +167,7 @@
   "workspaces": {
     "packages": [
       "packages/*",
+      "external/*",
       "external/*/packages/*",
       "."
     ],