diff --git a/src/core/polyfills.js b/src/core/polyfills.js
index f1de8a1fa..2ef0afce6 100644
--- a/src/core/polyfills.js
+++ b/src/core/polyfills.js
@@ -3,8 +3,13 @@
 // SubmitEvent.submitter polyfill for Safari < 15.4 and jsDOM
 // Original code: https://stackoverflow.com/a/61110260/1337474
 // Also see: https://caniuse.com/?search=submitter
-//
+// NOTE: the `submitter` property is now widely available except for ancient browsers and jsDOM.
 !(function () {
+    if (window.SubmitEvent && "submitter" in window.SubmitEvent.prototype) {
+        // `submitter` attribute is already supported.
+        return;
+    }
+
     let last_btn = null;
     const submitable_buttons = `button, input[type="button"], input[type="submit"], input[type="image"]`;
     document.addEventListener(
diff --git a/webpack/webpack.config.js b/webpack/webpack.config.js
index cd6ce4479..38a0f46f9 100644
--- a/webpack/webpack.config.js
+++ b/webpack/webpack.config.js
@@ -46,10 +46,6 @@ module.exports = () => {
     config.plugins.push(
         new CopyPlugin({
             patterns: [
-                // Copy polyfills loader to the output path.
-                // TODO: Polyfills not used anymore, remove for next major version.
-                { from: path.resolve(__dirname, "../src/polyfills-loader.js") },
-
                 // Build and copy Modernizr.
                 // We're abusing the CopyPlugin transform method here to build
                 // a Modernizr bundle using the modernizr config. The input