diff --git a/.changeset/gentle-bulldogs-heal.md b/.changeset/gentle-bulldogs-heal.md
new file mode 100644
index 000000000000..32c1d6714c43
--- /dev/null
+++ b/.changeset/gentle-bulldogs-heal.md
@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+fix: upgrade to esm-env 1.2.1 to fix issues with non-Vite setups
diff --git a/packages/svelte/package.json b/packages/svelte/package.json
index 6b3970c7f9e8..cd61ce2e8874 100644
--- a/packages/svelte/package.json
+++ b/packages/svelte/package.json
@@ -142,7 +142,7 @@
     "acorn-typescript": "^1.4.13",
     "aria-query": "^5.3.1",
     "axobject-query": "^4.1.0",
-    "esm-env": "^1.2.0",
+    "esm-env": "^1.2.1",
     "esrap": "^1.2.3",
     "is-reference": "^3.0.3",
     "locate-character": "^3.0.0",
diff --git a/packages/svelte/tests/runtime-browser/test.ts b/packages/svelte/tests/runtime-browser/test.ts
index 1b97988fdaf7..582a10edf722 100644
--- a/packages/svelte/tests/runtime-browser/test.ts
+++ b/packages/svelte/tests/runtime-browser/test.ts
@@ -79,6 +79,7 @@ async function run_test(
 			__CONFIG__: path.resolve(test_dir, '_config.js'),
 			'assert.js': assert_file
 		},
+		conditions: ['browser', 'production'],
 		plugins: [
 			{
 				name: 'testing-runtime-browser',
@@ -131,6 +132,7 @@ async function run_test(
 				__MAIN_DOT_SVELTE__: path.resolve(test_dir, 'main.svelte'),
 				__CONFIG__: path.resolve(test_dir, '_config.js')
 			},
+			conditions: ['browser', 'production'],
 			plugins: [
 				{
 					name: 'testing-runtime-browser-ssr',
@@ -191,9 +193,11 @@ async function run_test(
 
 	try {
 		const page = await browser.newPage();
-		page.on('console', (type) => {
+		page.on('console', (message) => {
+			let method = message.type();
+			if (method === 'warning') method = 'warn';
 			// @ts-ignore
-			console[type.type()](type.text());
+			console[method](message.text());
 		});
 
 		if (build_result_ssr) {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index bc431a4096ec..b604c59f20c6 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -81,8 +81,8 @@ importers:
         specifier: ^4.1.0
         version: 4.1.0
       esm-env:
-        specifier: ^1.2.0
-        version: 1.2.0
+        specifier: ^1.2.1
+        version: 1.2.1
       esrap:
         specifier: ^1.2.3
         version: 1.2.3
@@ -224,7 +224,7 @@ importers:
         version: 6.0.1(@lezer/common@1.2.1)
       esm-env:
         specifier: ^1.0.0
-        version: 1.2.0
+        version: 1.2.1
       marked:
         specifier: ^7.0.2
         version: 7.0.5
@@ -1442,8 +1442,8 @@ packages:
       jiti:
         optional: true
 
-  esm-env@1.2.0:
-    resolution: {integrity: sha512-OhSQuHL3mUcaQHjGe8UMG8GsJIJHYYz0flR0h9fiTPNMupLMkb7TvcRD0EeJXW5a8GHBgfz08b6FDLNK7kkPQA==}
+  esm-env@1.2.1:
+    resolution: {integrity: sha512-U9JedYYjCnadUlXk7e1Kr+aENQhtUaoaV9+gZm1T8LC/YBAPJx3NSPIAurFOC0U5vrdSevnUJS2/wUVxGwPhng==}
 
   espree@10.1.0:
     resolution: {integrity: sha512-M1M6CpiE6ffoigIOWYO9UDP8TMUw9kqb21tf+08IgDYjCsOvCuDt4jQcZmoYxx+w7zlKw9/N0KXfto+I8/FrXA==}
@@ -3519,7 +3519,7 @@ snapshots:
       '@types/cookie': 0.6.0
       cookie: 0.6.0
       devalue: 5.1.1
-      esm-env: 1.2.0
+      esm-env: 1.2.1
       import-meta-resolve: 4.1.0
       kleur: 4.1.5
       magic-string: 0.30.11
@@ -3534,7 +3534,7 @@ snapshots:
   '@sveltejs/site-kit@6.0.0-next.64(@sveltejs/kit@2.8.3(@sveltejs/vite-plugin-svelte@4.0.0-next.6(svelte@packages+svelte)(vite@5.4.6(@types/node@20.12.7)(lightningcss@1.23.0)(sass@1.70.0)(terser@5.27.0)))(svelte@packages+svelte)(vite@5.4.6(@types/node@20.12.7)(lightningcss@1.23.0)(sass@1.70.0)(terser@5.27.0)))(svelte@packages+svelte)':
     dependencies:
       '@sveltejs/kit': 2.8.3(@sveltejs/vite-plugin-svelte@4.0.0-next.6(svelte@packages+svelte)(vite@5.4.6(@types/node@20.12.7)(lightningcss@1.23.0)(sass@1.70.0)(terser@5.27.0)))(svelte@packages+svelte)(vite@5.4.6(@types/node@20.12.7)(lightningcss@1.23.0)(sass@1.70.0)(terser@5.27.0))
-      esm-env: 1.2.0
+      esm-env: 1.2.1
       svelte: link:packages/svelte
       svelte-persisted-store: 0.9.2(svelte@packages+svelte)
 
@@ -4182,7 +4182,7 @@ snapshots:
     transitivePeerDependencies:
       - supports-color
 
-  esm-env@1.2.0: {}
+  esm-env@1.2.1: {}
 
   espree@10.1.0:
     dependencies: