From bd8d044ada7d4e2108ad60615badd3702b8c0307 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nacho=20Codo=C3=B1er?= <igcogi@gmail.com>
Date: Wed, 19 Nov 2025 15:36:17 +0100
Subject: [PATCH] add legacy build configuration for SWC transpile and
 minification to fix issues on legacy bundles

---
 packages/babel-compiler/babel-compiler.js     | 24 +++++++++----------
 .../standard-minifier-js/plugin/minify-js.js  |  2 ++
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/packages/babel-compiler/babel-compiler.js b/packages/babel-compiler/babel-compiler.js
index ad0a8c295e..318f1e6c8a 100644
--- a/packages/babel-compiler/babel-compiler.js
+++ b/packages/babel-compiler/babel-compiler.js
@@ -142,16 +142,6 @@ BCp.initializeMeteorAppSwcrc = function () {
   return lastModifiedSwcConfig;
 };
 
-let lastModifiedSwcLegacyConfig;
-BCp.initializeMeteorAppLegacyConfig = function () {
-  const swcLegacyConfig = convertBabelTargetsForSwc(Babel.getMinimumModernBrowserVersions());
-  if (this.isVerbose() && !lastModifiedSwcLegacyConfig) {
-    logConfigBlock('SWC Legacy Config', swcLegacyConfig);
-  }
-  lastModifiedSwcLegacyConfig = swcLegacyConfig;
-  return lastModifiedSwcConfig;
-};
-
 // Helper function to check if @swc/helpers is available
 function hasSwcHelpers() {
   return fs.existsSync(`${getMeteorAppDir()}/node_modules/@swc/helpers`);
@@ -196,7 +186,6 @@ BCp.processFilesForTarget = function (inputFiles) {
 
   this.initializeMeteorAppConfig();
   this.initializeMeteorAppSwcrc();
-  this.initializeMeteorAppLegacyConfig();
   this.initializeMeteorAppSwcHelpersAvailable();
 
   inputFiles.forEach(function (inputFile) {
@@ -382,7 +371,18 @@ if (Plugin?.rspackHelpers?.isRspackOutputFile(inputFilePath)) {
         sourceFileName: filename,
         ...(isLegacyWebArch && {
           env: {
-            targets: lastModifiedSwcLegacyConfig || {},
+            targets: {
+              chrome: '49',
+              edge: '15',
+              firefox: '30',
+              safari: '10',
+              ios: '10',
+              android: '5',
+              opera: '42',
+              ie: '11',
+              node: '8',
+              electron: '1.6',
+            },
             mode: 'entry',
             coreJs: '3.37',
           },
diff --git a/packages/standard-minifier-js/plugin/minify-js.js b/packages/standard-minifier-js/plugin/minify-js.js
index 0fe5ca613f..9b0ebd42de 100644
--- a/packages/standard-minifier-js/plugin/minify-js.js
+++ b/packages/standard-minifier-js/plugin/minify-js.js
@@ -49,6 +49,7 @@ export class MeteorMinifier {
       const NODE_ENV = process.env.NODE_ENV || 'development';
       
       let content = file.getContentsAsString();
+      const isLegacyBuild = file?._arch === 'web.browser.legacy';
 
       return swc.minifySync(
         content,
@@ -60,6 +61,7 @@ export class MeteorMinifier {
             unused: true,
             dead_code: true,
             typeofs: false,
+            ...(isLegacyBuild && { defaults: false }),
 
             global_defs: {
               'process.env.NODE_ENV': NODE_ENV,