diff --git a/package-lock.json b/package-lock.json
index 04851ce3d..87432ea44 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -36,7 +36,7 @@
         "babel-loader": "9.1.2",
         "codecov": "^3.8.3",
         "concurrently": "7.4.0",
-        "core-js": "3.30.2",
+        "core-js": "3.27.1",
         "cpx2": "4.2.3",
         "eslint": "^7.32.0",
         "eslint-plugin-no-jquery": "^2.7.0",
@@ -5640,10 +5640,11 @@
       }
     },
     "node_modules/core-js": {
-      "version": "3.30.2",
+      "version": "3.27.1",
+      "resolved": "https://registry.npmjs.org/core-js/-/core-js-3.27.1.tgz",
+      "integrity": "sha512-GutwJLBChfGCpwwhbYoqfv03LAfmiz7e7D/BNxzeMxwQf10GRSzqiOjx7AmtEk+heiD/JWmBuyBPgFtx0Sg1ww==",
       "dev": true,
       "hasInstallScript": true,
-      "license": "MIT",
       "funding": {
         "type": "opencollective",
         "url": "https://opencollective.com/core-js"
@@ -19094,7 +19095,9 @@
       "dev": true
     },
     "core-js": {
-      "version": "3.30.2",
+      "version": "3.27.1",
+      "resolved": "https://registry.npmjs.org/core-js/-/core-js-3.27.1.tgz",
+      "integrity": "sha512-GutwJLBChfGCpwwhbYoqfv03LAfmiz7e7D/BNxzeMxwQf10GRSzqiOjx7AmtEk+heiD/JWmBuyBPgFtx0Sg1ww==",
       "dev": true
     },
     "core-js-compat": {
diff --git a/package.json b/package.json
index 5780b9eea..32bb585bf 100644
--- a/package.json
+++ b/package.json
@@ -52,7 +52,7 @@
     "babel-loader": "9.1.2",
     "codecov": "^3.8.3",
     "concurrently": "7.4.0",
-    "core-js": "3.30.2",
+    "core-js": "3.27.1",
     "cpx2": "4.2.3",
     "eslint": "^7.32.0",
     "eslint-plugin-no-jquery": "^2.7.0",
@@ -121,7 +121,7 @@
     "DOCS:update:test-deps": "If CI succeeds, these should be good to update",
     "update:test-deps": "npm i @babel/eslint-parser@latest @open-wc/testing-helpers@latest @types/jest@latest codecov@latest eslint@7 eslint-plugin-testcafe@latest jest@latest sinon@latest testcafe@latest",
     "DOCS:update:build-deps": "These can cause strange changes, so do an npm run build + check file size (git diff --stat), and check the site is as expected",
-    "update:build-deps": "npm i @babel/core@latest @babel/preset-env@latest @babel/plugin-proposal-class-properties@latest @babel/plugin-proposal-decorators@latest babel-loader@latest core-js@latest regenerator-runtime@latest sass@latest svgo@latest webpack@latest webpack-cli@latest",
+    "update:build-deps": "npm i @babel/core@latest @babel/preset-env@latest @babel/plugin-proposal-class-properties@latest @babel/plugin-proposal-decorators@latest babel-loader@latest core-js@3.27.1 regenerator-runtime@latest sass@latest svgo@latest webpack@latest webpack-cli@latest",
     "codecov": "npx codecov"
   }
 }