diff --git a/.changeset/orange-vans-trade.md b/.changeset/orange-vans-trade.md
new file mode 100644
index 000000000..a69c53c3f
--- /dev/null
+++ b/.changeset/orange-vans-trade.md
@@ -0,0 +1,5 @@
+---
+'wmr': patch
+---
+
+Fix case where deduped css would crash the bundle
diff --git a/.github/ISSUE_TEMPLATE/bug_report.md b/.github/ISSUE_TEMPLATE/bug_report.md
index e8051a803..6ed29c7eb 100644
--- a/.github/ISSUE_TEMPLATE/bug_report.md
+++ b/.github/ISSUE_TEMPLATE/bug_report.md
@@ -4,7 +4,6 @@ about: Create a report to help us improve
 title: ''
 labels: bug
 assignees: ''
-
 ---
 
 <!--
@@ -16,6 +15,7 @@ A clear and concise description of what the bug is.
 
 **To Reproduce**
 Steps to reproduce the behavior:
+
 1. Go to '...'
 2. Click on '....'
 3. Scroll down to '....'
@@ -25,9 +25,10 @@ Steps to reproduce the behavior:
 A clear and concise description of what you expected to happen.
 
 **Desktop (please complete the following information):**
- - OS: [e.g. iOS]
- - Browser [e.g. chrome, safari]
- - WMR Version [e.g. 22]
+
+- OS: [e.g. iOS]
+- Browser [e.g. chrome, safari]
+- WMR Version [e.g. 22]
 
 **Additional context**
 Add any other context about the problem here.
diff --git a/.github/ISSUE_TEMPLATE/feature_request.md b/.github/ISSUE_TEMPLATE/feature_request.md
index 946858a85..0e2fc90be 100644
--- a/.github/ISSUE_TEMPLATE/feature_request.md
+++ b/.github/ISSUE_TEMPLATE/feature_request.md
@@ -4,7 +4,6 @@ about: Suggest an idea for this project
 title: ''
 labels: enhancement
 assignees: ''
-
 ---
 
 <!--
diff --git a/packages/wmr/src/lib/cssnano-lite.js b/packages/wmr/src/lib/cssnano-lite.js
index 4f7ffcc1c..0d7b3aebb 100644
--- a/packages/wmr/src/lib/cssnano-lite.js
+++ b/packages/wmr/src/lib/cssnano-lite.js
@@ -3,6 +3,7 @@
  * This is essentially the same plugins, but without SVGO.
  */
 import postcss from 'postcss';
+import cssDeclarationSorter from 'css-declaration-sorter';
 import discardComments from 'postcss-discard-comments';
 import postcssReduceInitial from 'postcss-reduce-initial';
 import postcssReduceTransforms from 'postcss-reduce-transforms';
@@ -30,6 +31,7 @@ import postcssNormalizeTimingFunctions from 'postcss-normalize-timing-functions'
 
 const rawCache = postcss.plugin('cssnano-util-raw-cache', () => {
 	return (css, result) => {
+		// @ts-ignore-next
 		result.root.rawCache = {
 			colon: ':',
 			indent: '',
@@ -50,27 +52,28 @@ const plugins = [
 	discardComments,
 	postcssReduceInitial,
 	postcssReduceTransforms,
-	postcssConvertValues,
-	postcssCalc,
+	postcssNormalizeDisplayValues,
 	postcssColormin,
+	postcssNormalizeTimingFunctions,
+	postcssCalc,
+	postcssConvertValues,
 	postcssOrderedValues,
 	postcssMinifySelectors,
 	postcssMinifyParams,
+	postcssDiscardOverridden,
+	postcssNormalizeString,
+	postcssNormalizeUnicode,
 	postcssMinifyFontValues,
 	postcssNormalizeUrl,
+	postcssNormalizeRepeatStyle,
+	postcssNormalizePositions,
+	postcssNormalizeWhitespace,
 	postcssMergeLonghand,
 	postcssDiscardDuplicates,
-	postcssDiscardOverridden,
-	postcssNormalizeRepeatStyle,
 	postcssMergeRules,
 	postcssDiscardEmpty,
 	postcssUniqueSelectors,
-	postcssNormalizeString,
-	postcssNormalizePositions,
-	postcssNormalizeWhitespace,
-	postcssNormalizeUnicode,
-	postcssNormalizeDisplayValues,
-	postcssNormalizeTimingFunctions,
+	cssDeclarationSorter,
 	rawCache
 ].map(fn => (fn && fn.default) || fn);
 
diff --git a/packages/wmr/src/plugins/optimize-graph-plugin.js b/packages/wmr/src/plugins/optimize-graph-plugin.js
index 12dfff8c5..ce6405b6e 100644
--- a/packages/wmr/src/plugins/optimize-graph-plugin.js
+++ b/packages/wmr/src/plugins/optimize-graph-plugin.js
@@ -29,6 +29,7 @@ export default function optimizeGraphPlugin({ publicPath = '', cssMinSize = 1000
 			mergeAdjacentCss(graph);
 			hoistCascadedCss(graph, { cssMinSize });
 			hoistEntryCss(graph);
+			graph.commit();
 			hoistTransitiveImports(graph);
 		}
 	};
@@ -42,6 +43,7 @@ export default function optimizeGraphPlugin({ publicPath = '', cssMinSize = 1000
 class ChunkGraph {
 	constructor(bundle, { publicPath }) {
 		this.bundle = bundle;
+		this.bundleRemoved = new Set();
 		this.assetToChunkMap = constructAssetToChunkMap(bundle);
 		this.entries = this.findEntryChunks();
 		this.meta = new Map();
@@ -49,6 +51,12 @@ class ChunkGraph {
 		// this.entryAssets = this.findEntryAssets();
 	}
 
+	commit() {
+		this.bundleRemoved.forEach(f => {
+			delete this.bundle[f];
+		});
+	}
+
 	/**
 	 * Get a mutable object for storing metadata about a chunk/asset.
 	 * @param {string} fileName
diff --git a/packages/wmr/test/fixtures.test.js b/packages/wmr/test/fixtures.test.js
index 0af312d19..c3c9c31d1 100644
--- a/packages/wmr/test/fixtures.test.js
+++ b/packages/wmr/test/fixtures.test.js
@@ -203,163 +203,171 @@ describe('fixtures', () => {
 
 		const timeout = n => new Promise(r => setTimeout(r, n));
 
-		it('should hot reload the child-file', async () => {
-			await loadFixture('hmr', env);
-			instance = await runWmrFast(env.tmp.path);
-			await getOutput(env, instance);
+		async function waitForText(element, text, timeoutAfter = 5000) {
+			const start = Date.now();
+			let t;
+			while (Date.now() - start < timeoutAfter) {
+				t = await element.evaluate(el => el.textContent);
+				if (t === text) break;
+				await timeout(100);
+			}
+			return t;
+		}
 
-			const home = await env.page.$('.home');
-			let text = home ? await home.evaluate(el => el.textContent) : null;
-			expect(text).toEqual('Home');
+		async function waitForValue(page, fn, value) {
+			return (await page.waitForFunction(`value => (${fn})() === value`, { timeout: 1000 }, value)) && value;
+		}
 
-			await updateFile(env.tmp.path, 'home.js', content =>
-				content.replace('<p class="home">Home</p>', '<p class="home">Away</p>')
-			);
+		describe('JavaScript', () => {
+			it('should bubble up updates in non-accepted files', async () => {
+				await loadFixture('hmr', env);
+				instance = await runWmrFast(env.tmp.path);
+				await getOutput(env, instance);
+
+				const count = await env.page.$('.count');
+				let text = count ? await count.evaluate(el => el.textContent) : null;
+				expect(text).toEqual('0');
+
+				let increment = await env.page.$('.increment');
+				// @ts-ignore-next
+				await increment.click();
+				text = count ? await count.evaluate(el => el.textContent) : null;
+				expect(text).toEqual('1');
+
+				await updateFile(env.tmp.path, 'useCounter.js', content =>
+					content.replace('() => setCount(count + 1)', '() => setCount(count + 2)')
+				);
+
+				await timeout(2000);
+
+				increment = await env.page.$('.increment');
+				// @ts-ignore-next
+				await increment.click();
+				text = count ? await count.evaluate(el => el.textContent) : null;
+				expect(text).toEqual('3');
+			});
 
-			await timeout(1000);
+			it('should bubble up updates in non-accepted files with multiple parents', async () => {
+				await loadFixture('hmr', env);
+				instance = await runWmrFast(env.tmp.path);
+				await getOutput(env, instance);
 
-			text = home ? await home.evaluate(el => el.textContent) : null;
-			expect(text).toEqual('Away');
-		});
+				let homeFoo = await env.page.$('#home-foo');
+				let rootFoo = await env.page.$('#root-foo');
+				let homeText = homeFoo ? await homeFoo.evaluate(el => el.textContent) : null;
+				let rootText = rootFoo ? await rootFoo.evaluate(el => el.textContent) : null;
+				expect(homeText).toEqual('42');
+				expect(rootText).toEqual('42');
 
-		it('should bubble up updates in non-accepted files', async () => {
-			await loadFixture('hmr', env);
-			instance = await runWmrFast(env.tmp.path);
-			await getOutput(env, instance);
+				await updateFile(env.tmp.path, 'store.js', content => content.replace('42', '43'));
 
-			const count = await env.page.$('.count');
-			let text = count ? await count.evaluate(el => el.textContent) : null;
-			expect(text).toEqual('0');
+				await timeout(2000);
 
-			let increment = await env.page.$('.increment');
-			await increment.click();
-			text = count ? await count.evaluate(el => el.textContent) : null;
-			expect(text).toEqual('1');
+				homeFoo = await env.page.$('#home-foo');
+				rootFoo = await env.page.$('#root-foo');
+				homeText = homeFoo ? await homeFoo.evaluate(el => el.textContent) : null;
+				rootText = rootFoo ? await rootFoo.evaluate(el => el.textContent) : null;
+				expect(homeText).toEqual('43');
+				expect(rootText).toEqual('43');
+			});
 
-			await updateFile(env.tmp.path, 'useCounter.js', content =>
-				content.replace('() => setCount(count + 1)', '() => setCount(count + 2)')
-			);
+			it('should hot reload for an updated file', async () => {
+				await loadFixture('hmr', env);
+				instance = await runWmrFast(env.tmp.path);
+				await getOutput(env, instance);
 
-			await timeout(2000);
+				const home = await env.page.$('.home');
+				expect(await waitForText(home, 'Home', 1000)).toEqual('Home');
 
-			increment = await env.page.$('.increment');
-			await increment.click();
-			text = count ? await count.evaluate(el => el.textContent) : null;
-			expect(text).toEqual('3');
-		});
+				await updateFile(env.tmp.path, 'home.js', content =>
+					content.replace('<p class="home">Home</p>', '<p class="home">Away</p>')
+				);
 
-		it('should bubble up updates in non-accepted files with multiple parents', async () => {
-			await loadFixture('hmr', env);
-			instance = await runWmrFast(env.tmp.path);
-			await getOutput(env, instance);
+				expect(await waitForText(home, 'Away', 5000)).toEqual('Away');
+			});
 
-			let homeFoo = await env.page.$('#home-foo');
-			let rootFoo = await env.page.$('#root-foo');
-			let homeText = homeFoo ? await homeFoo.evaluate(el => el.textContent) : null;
-			let rootText = rootFoo ? await rootFoo.evaluate(el => el.textContent) : null;
-			expect(homeText).toEqual('42');
-			expect(rootText).toEqual('42');
+			it('should hot reload for a newly created file', async () => {
+				await loadFixture('hmr', env);
+				instance = await runWmrFast(env.tmp.path);
+				await getOutput(env, instance);
 
-			await updateFile(env.tmp.path, 'store.js', content => content.replace('42', '43'));
+				const home = await env.page.waitForSelector('.home', { timeout: 1000 });
+				expect(home.evaluate(el => el.textContent)).toEqual('Home');
 
-			await timeout(2000);
+				const compPath = path.join(env.tmp.path, 'child.js');
+				await fs.writeFile(compPath, `export default function Child() {return <p class="child">child</p>}`);
 
-			homeFoo = await env.page.$('#home-foo');
-			rootFoo = await env.page.$('#root-foo');
-			homeText = homeFoo ? await homeFoo.evaluate(el => el.textContent) : null;
-			rootText = rootFoo ? await rootFoo.evaluate(el => el.textContent) : null;
-			expect(homeText).toEqual('43');
-			expect(rootText).toEqual('43');
-		});
+				await timeout(1000);
 
-		it('should hot reload for a newly created file', async () => {
-			await loadFixture('hmr', env);
-			instance = await runWmrFast(env.tmp.path);
-			await getOutput(env, instance);
+				expect(await home.evaluate(el => el.textContent)).toEqual('Home');
 
-			const compPath = path.join(env.tmp.path, 'child.js');
-			await fs.writeFile(compPath, `export default function Child() {return <p class="child">child</p>}`);
+				await updateFile(env.tmp.path, 'home.js', content => {
+					const newContent = `import Child from './child.js';\n\n${content}`;
+					return newContent.replace('<p class="home">Home</p>', '<Child />');
+				});
 
-			const home = await env.page.$('.home');
-			let text = home ? await home.evaluate(el => el.textContent) : null;
-			expect(text).toEqual('Home');
+				const child = await env.page.waitForSelector('.child', { timeout: 1000 });
+				expect(await child.evaluate(el => el.textContent)).toEqual('child');
 
-			await updateFile(env.tmp.path, 'home.js', content => {
-				const newContent = `import Child from './child.js';\n\n${content}`;
-				return newContent.replace('<p class="home">Home</p>', '<Child />');
+				// Ensure we're still on the page and haven't navigated away:
+				expect(await home.evaluate(el => el.textContent)).toEqual('Home');
 			});
-
-			await timeout(1000);
-
-			const child = await env.page.$('.child');
-			text = child ? await child.evaluate(el => el.textContent) : null;
-			expect(text).toEqual('child');
 		});
 
-		it('should hot reload a css-file imported from index.html', async () => {
-			await loadFixture('hmr', env);
-			instance = await runWmrFast(env.tmp.path);
-			await getOutput(env, instance);
-
-			expect(await page.$eval('body', e => getComputedStyle(e).color)).toBe('rgb(51, 51, 51)');
+		describe('CSS', () => {
+			it('should hot reload a css-file imported from index.html', async () => {
+				await loadFixture('hmr', env);
+				instance = await runWmrFast(env.tmp.path);
+				await getOutput(env, instance);
 
-			await updateFile(env.tmp.path, 'index.css', content => content.replace('color: #333;', 'color: #000;'));
+				expect(await page.$eval('body', e => getComputedStyle(e).color)).toBe('rgb(51, 51, 51)');
 
-			await timeout(1000);
-
-			expect(await page.$eval('body', e => getComputedStyle(e).color)).toBe('rgb(0, 0, 0)');
-		});
+				await updateFile(env.tmp.path, 'index.css', content => content.replace('color: #333;', 'color: #000;'));
 
-		it('should hot reload a module css-file', async () => {
-			await loadFixture('hmr', env);
-			instance = await runWmrFast(env.tmp.path);
-			await getOutput(env, instance);
+				expect(await waitForValue(page, () => getComputedStyle(document.body), 'rgb(0, 0, 0)')).toBe('rgb(0, 0, 0)');
+			});
 
-			expect(await page.$eval('main', e => getComputedStyle(e).color)).toBe('rgb(51, 51, 51)');
+			it('should hot reload a module css-file', async () => {
+				await loadFixture('hmr', env);
+				instance = await runWmrFast(env.tmp.path);
+				await getOutput(env, instance);
 
-			await updateFile(env.tmp.path, 'style.module.css', content => content.replace('color: #333;', 'color: #000;'));
+				expect(await page.$eval('main', e => getComputedStyle(e).color)).toBe('rgb(51, 51, 51)');
 
-			await timeout(1000);
+				await updateFile(env.tmp.path, 'style.module.css', content => content.replace('color: #333;', 'color: #000;'));
 
-			expect(await page.$eval('main', e => getComputedStyle(e).color)).toBe('rgb(0, 0, 0)');
+				expect(await waitForValue(page, () => getComputedStyle(document.querySelector('main')), 'rgb(0, 0, 0)')).toBe(
+					'rgb(0, 0, 0)'
+				);
+			});
 		});
-	});
-
-	describe('hmr-scss', () => {
-		async function updateFile(tempDir, file, replacer) {
-			const compPath = path.join(tempDir, file);
-			const content = await fs.readFile(compPath, 'utf-8');
-			await fs.writeFile(compPath, replacer(content));
-		}
 
-		const timeout = n => new Promise(r => setTimeout(r, n));
-
-		it('should hot reload an scss-file imported from index.html', async () => {
-			await loadFixture('hmr-scss', env);
-			instance = await runWmrFast(env.tmp.path);
-			await getOutput(env, instance);
-
-			expect(await page.$eval('body', e => getComputedStyle(e).color)).toBe('rgb(51, 51, 51)');
+		describe('SCSS', () => {
+			it('should hot reload an scss-file imported from index.html', async () => {
+				await loadFixture('hmr-scss', env);
+				instance = await runWmrFast(env.tmp.path);
+				await getOutput(env, instance);
 
-			await updateFile(env.tmp.path, 'index.scss', content => content.replace('color: #333;', 'color: #000;'));
+				expect(await page.$eval('body', e => getComputedStyle(e).color)).toBe('rgb(51, 51, 51)');
 
-			await timeout(1000);
+				await updateFile(env.tmp.path, 'index.scss', content => content.replace('color: #333;', 'color: #000;'));
 
-			expect(await page.$eval('body', e => getComputedStyle(e).color)).toBe('rgb(0, 0, 0)');
-		});
-
-		it('should hot reload an imported scss-file from another scss-file', async () => {
-			await loadFixture('hmr-scss', env);
-			instance = await runWmrFast(env.tmp.path);
-			await getOutput(env, instance);
+				expect(await waitForValue(page, () => getComputedStyle(document.body), 'rgb(0, 0, 0)')).toBe('rgb(0, 0, 0)');
+			});
 
-			expect(await page.$eval('main', e => getComputedStyle(e).color)).toBe('rgb(51, 51, 51)');
+			it('should hot reload an imported scss-file from another scss-file', async () => {
+				await loadFixture('hmr-scss', env);
+				instance = await runWmrFast(env.tmp.path);
+				await getOutput(env, instance);
 
-			await updateFile(env.tmp.path, 'home.scss', content => content.replace('color: #333;', 'color: #000;'));
+				expect(await page.$eval('main', e => getComputedStyle(e).color)).toBe('rgb(51, 51, 51)');
 
-			await timeout(1000);
+				await updateFile(env.tmp.path, 'home.scss', content => content.replace('color: #333;', 'color: #000;'));
 
-			expect(await page.$eval('main', e => getComputedStyle(e).color)).toBe('rgb(0, 0, 0)');
+				expect(await waitForValue(page, () => getComputedStyle(document.querySelector('main')), 'rgb(0, 0, 0)')).toBe(
+					'rgb(0, 0, 0)'
+				);
+			});
 		});
 	});
 
diff --git a/packages/wmr/test/production.test.js b/packages/wmr/test/production.test.js
index e947cf05a..d80cab51b 100644
--- a/packages/wmr/test/production.test.js
+++ b/packages/wmr/test/production.test.js
@@ -316,13 +316,11 @@ describe('production', () => {
 				waitUntil: ['networkidle0', 'load']
 			});
 
-			expect(logs).toEqual([
-				`hello from index.js`,
-				`hello from page one`,
-				`hello from page two`,
-				`loaded pages`,
-				`page one,page two`
-			]);
+			expect(logs).toContain(`hello from index.js`);
+			expect(logs).toContain(`hello from page one`);
+			expect(logs).toContain(`hello from page two`);
+			expect(logs).toContain(`loaded pages`);
+			expect(logs).toContain(`page one,page two`);
 		});
 	});