diff --git a/CHANGELOG.md b/CHANGELOG.md
index d9ec5900b4..59fa25682e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@
 * Allow access to `let:` variables in sibling attributes on slot root ([#4173](https://github.com/sveltejs/svelte/issues/4173))
 * Fix `~=` and class selector matching against values separated by any whitespace characters ([#4242](https://github.com/sveltejs/svelte/issues/4242))
 * Fix code generation for `await`ed expressions that need parentheses ([#4267](https://github.com/sveltejs/svelte/issues/4267))
+* Preserve JavaScript comments from the original component source where possible ([#4268](https://github.com/sveltejs/svelte/issues/4268))
 * Add some more known globals ([#4276](https://github.com/sveltejs/svelte/pull/4276))
 * Correctly apply event modifiers to `<svelte:body>` events ([#4278](https://github.com/sveltejs/svelte/issues/4278))
 
diff --git a/package-lock.json b/package-lock.json
index 4d902d5c48..90f5a331ed 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -597,9 +597,9 @@
       "dev": true
     },
     "code-red": {
-      "version": "0.0.30",
-      "resolved": "https://registry.npmjs.org/code-red/-/code-red-0.0.30.tgz",
-      "integrity": "sha512-nsScy3A59tbV5uzndcedIEGHmdWNEByJrC7DUyb0Wh7qZcoPfAlcYsr0ZINkAEhZofSI26F1mi+lRO0/6EV2/g==",
+      "version": "0.0.31",
+      "resolved": "https://registry.npmjs.org/code-red/-/code-red-0.0.31.tgz",
+      "integrity": "sha512-7Gf3vm8pDbs+H/hKsaqOZe0xKlE9Neah12GCfs7qun3fBUaOXwexAMjn0Eo9cvJJvhRMaL0jgPiY9ZGLTWoe8A==",
       "dev": true,
       "requires": {
         "acorn": "^7.1.0",
diff --git a/package.json b/package.json
index 671a7e5025..6a66276c2d 100644
--- a/package.json
+++ b/package.json
@@ -70,7 +70,7 @@
     "acorn": "^7.1.0",
     "agadoo": "^1.1.0",
     "c8": "^5.0.1",
-    "code-red": "0.0.30",
+    "code-red": "0.0.31",
     "codecov": "^3.5.0",
     "css-tree": "1.0.0-alpha22",
     "eslint": "^6.3.0",
diff --git a/src/compiler/parse/acorn.ts b/src/compiler/parse/acorn.ts
index 30ab3c398c..d14721cdab 100644
--- a/src/compiler/parse/acorn.ts
+++ b/src/compiler/parse/acorn.ts
@@ -1,14 +1,13 @@
-import * as acorn from 'acorn';
+import { Node } from 'acorn';
+import * as code_red from 'code-red';
 
-const Parser = acorn.Parser;
-
-export const parse = (source: string) => Parser.parse(source, {
+export const parse = (source: string): Node => code_red.parse(source, {
 	sourceType: 'module',
 	ecmaVersion: 11,
 	locations: true
 });
 
-export const parse_expression_at = (source: string, index: number) => Parser.parseExpressionAt(source, index, {
+export const parse_expression_at = (source: string, index: number): Node => code_red.parseExpressionAt(source, index, {
 	ecmaVersion: 11,
 	locations: true
 });
\ No newline at end of file
diff --git a/test/js/samples/action-custom-event-handler/expected.js b/test/js/samples/action-custom-event-handler/expected.js
index 968b5965d5..ead6d90e06 100644
--- a/test/js/samples/action-custom-event-handler/expected.js
+++ b/test/js/samples/action-custom-event-handler/expected.js
@@ -43,7 +43,7 @@ function handleFoo(bar) {
 
 function foo(node, callback) {
 	
-}
+} // code goes here
 
 function instance($$self, $$props, $$invalidate) {
 	let { bar } = $$props;
diff --git a/test/js/samples/collapses-text-around-comments/expected.js b/test/js/samples/collapses-text-around-comments/expected.js
index 8c0e9d5373..6fef0f9490 100644
--- a/test/js/samples/collapses-text-around-comments/expected.js
+++ b/test/js/samples/collapses-text-around-comments/expected.js
@@ -63,4 +63,4 @@ class Component extends SvelteComponent {
 	}
 }
 
-export default Component;
+export default Component;
\ No newline at end of file
diff --git a/test/js/samples/css-media-query/expected.js b/test/js/samples/css-media-query/expected.js
index 0566c22ddd..f477670059 100644
--- a/test/js/samples/css-media-query/expected.js
+++ b/test/js/samples/css-media-query/expected.js
@@ -46,4 +46,4 @@ class Component extends SvelteComponent {
 	}
 }
 
-export default Component;
+export default Component;
\ No newline at end of file
diff --git a/test/js/samples/event-modifiers/expected.js b/test/js/samples/event-modifiers/expected.js
index 252034a431..c12c3523a0 100644
--- a/test/js/samples/event-modifiers/expected.js
+++ b/test/js/samples/event-modifiers/expected.js
@@ -63,11 +63,11 @@ function create_fragment(ctx) {
 
 function handleTouchstart() {
 	
-}
+} // ...
 
 function handleClick() {
 	
-}
+} // ...
 
 class Component extends SvelteComponent {
 	constructor(options) {
diff --git a/test/js/samples/ssr-no-oncreate-etc/expected.js b/test/js/samples/ssr-no-oncreate-etc/expected.js
index 276587eeca..803f06a882 100644
--- a/test/js/samples/ssr-no-oncreate-etc/expected.js
+++ b/test/js/samples/ssr-no-oncreate-etc/expected.js
@@ -13,7 +13,7 @@ function foo() {
 
 function swipe(node, callback) {
 	
-}
+} // TODO implement
 
 const Component = create_ssr_component(($$result, $$props, $$bindings, $$slots) => {
 	onMount(() => {
diff --git a/test/parser/samples/script-comment-only/output.json b/test/parser/samples/script-comment-only/output.json
index 3441d8a7bb..e090b30ae6 100644
--- a/test/parser/samples/script-comment-only/output.json
+++ b/test/parser/samples/script-comment-only/output.json
@@ -41,7 +41,15 @@
 				}
 			},
 			"body": [],
-			"sourceType": "module"
+			"sourceType": "module",
+			"trailingComments": [
+				{
+					"type": "Line",
+					"value": " TODO write some code",
+					"start": 10,
+					"end": 33
+				}
+			]
 		}
 	}
 }
\ No newline at end of file
diff --git a/test/parser/samples/script-comment-trailing-multiline/output.json b/test/parser/samples/script-comment-trailing-multiline/output.json
index 3c02b1fbde..be83eeea8b 100644
--- a/test/parser/samples/script-comment-trailing-multiline/output.json
+++ b/test/parser/samples/script-comment-trailing-multiline/output.json
@@ -134,7 +134,15 @@
 					"kind": "let"
 				}
 			],
-			"sourceType": "module"
+			"sourceType": "module",
+			"trailingComments": [
+				{
+					"type": "Block",
+					"value": "\n\ttrailing multiline comment\n",
+					"start": 32,
+					"end": 67
+				}
+			]
 		}
 	}
 }
\ No newline at end of file
diff --git a/test/parser/samples/script-comment-trailing/output.json b/test/parser/samples/script-comment-trailing/output.json
index beca001042..a2bc00bc00 100644
--- a/test/parser/samples/script-comment-trailing/output.json
+++ b/test/parser/samples/script-comment-trailing/output.json
@@ -134,7 +134,15 @@
 					"kind": "let"
 				}
 			],
-			"sourceType": "module"
+			"sourceType": "module",
+			"trailingComments": [
+				{
+					"type": "Line",
+					"value": " trailing line comment",
+					"start": 32,
+					"end": 56
+				}
+			]
 		}
 	}
 }
\ No newline at end of file