diff --git a/demos/react/package.json b/demos/react/package.json
index 5a16ef5cba..871b71ee2d 100644
--- a/demos/react/package.json
+++ b/demos/react/package.json
@@ -84,7 +84,6 @@
     "@types/text-encoding-utf-8": "^1.0.5",
     "@vitejs/plugin-react": "^4.5.0",
     "cross-env": "catalog:",
-    "custom-event-polyfill": "^1.0.7",
     "globals": "catalog:",
     "react-router-dom": "^7.6.1",
     "regenerator-runtime": "^0.14.1",
diff --git a/frameworks/angular-slickgrid/package.json b/frameworks/angular-slickgrid/package.json
index d51b08fd05..d5876f18de 100644
--- a/frameworks/angular-slickgrid/package.json
+++ b/frameworks/angular-slickgrid/package.json
@@ -110,7 +110,6 @@
     "@vitest/coverage-v8": "catalog:",
     "angular-eslint": "^19.6.0",
     "bootstrap": "catalog:",
-    "custom-event-polyfill": "^1.0.7",
     "cypress": "catalog:",
     "cypress-real-events": "catalog:",
     "dompurify": "catalog:",
diff --git a/frameworks/slickgrid-react/package.json b/frameworks/slickgrid-react/package.json
index 67b4e79f07..b2d5a25221 100644
--- a/frameworks/slickgrid-react/package.json
+++ b/frameworks/slickgrid-react/package.json
@@ -94,7 +94,6 @@
     "@types/react-dom": "^19.1.5",
     "@types/sortablejs": "^1.15.8",
     "@vitejs/plugin-react": "^4.5.0",
-    "custom-event-polyfill": "^1.0.7",
     "dompurify": "catalog:",
     "eslint-plugin-react": "^7.37.5",
     "eslint-plugin-react-hooks": "^5.2.0",
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index cdb999320e..c0aef5b8b7 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -457,9 +457,6 @@ importers:
       cross-env:
         specifier: 'catalog:'
         version: 7.0.3
-      custom-event-polyfill:
-        specifier: ^1.0.7
-        version: 1.0.7
       globals:
         specifier: 'catalog:'
         version: 16.1.0
@@ -829,9 +826,6 @@ importers:
       bootstrap:
         specifier: 'catalog:'
         version: 5.3.6(@popperjs/core@2.11.8)
-      custom-event-polyfill:
-        specifier: ^1.0.7
-        version: 1.0.7
       cypress:
         specifier: 'catalog:'
         version: 14.3.3
@@ -1033,9 +1027,6 @@ importers:
       '@vitejs/plugin-react':
         specifier: ^4.5.0
         version: 4.5.0(vite@6.3.5(@types/node@22.15.18)(jiti@2.4.2)(less@4.3.0)(sass-embedded@1.87.0)(sass@1.89.0)(stylus@0.64.0)(terser@5.39.0)(yaml@2.7.1))
-      custom-event-polyfill:
-        specifier: ^1.0.7
-        version: 1.0.7
       dompurify:
         specifier: 'catalog:'
         version: 3.2.5
@@ -6466,9 +6457,6 @@ packages:
   csstype@3.1.3:
     resolution: {integrity: sha512-M1uQkMl8rQK/szD0LNhtqxIPLpimGm8sOBwU7lLnCpSbTyY3yeU1Vc7l4KT5zT4s/yOxHH5O7tIuuLOCnLADRw==}
 
-  custom-event-polyfill@1.0.7:
-    resolution: {integrity: sha512-TDDkd5DkaZxZFM8p+1I3yAlvM3rSr1wbrOliG4yJiwinMZN8z/iGL7BTlDkrJcYTmgUSb4ywVCc3ZaUtOtC76w==}
-
   cypress-real-events@1.14.0:
     resolution: {integrity: sha512-XmI8y3OZLh6cjRroPalzzS++iv+pGCaD9G9kfIbtspgv7GVsDt30dkZvSXfgZb4rAN+3pOkMVB7e0j4oXydW7Q==}
     peerDependencies:
@@ -18286,8 +18274,6 @@ snapshots:
 
   csstype@3.1.3: {}
 
-  custom-event-polyfill@1.0.7: {}
-
   cypress-real-events@1.14.0(cypress@14.3.3):
     dependencies:
       cypress: 14.3.3