diff --git a/.github/lock.yml b/.github/lock.yml
deleted file mode 100644
index c80c7a0a09968..0000000000000
--- a/.github/lock.yml
+++ /dev/null
@@ -1,6 +0,0 @@
-# Configuration for lock-threads - https://github.com/dessant/lock-threads
-
-# Number of days of inactivity before a closed issue or pull request is locked
-daysUntilLock: 30
-# Comment to post before locking. Set to `false` to disable
-lockComment: 'This issue has been automatically locked due to no recent activity. If you are running into a similar issue, please open a new issue with a reproduction. Thank you.'
diff --git a/.github/workflows/lock.yml b/.github/workflows/lock.yml
new file mode 100644
index 0000000000000..c8df2516aa2c9
--- /dev/null
+++ b/.github/workflows/lock.yml
@@ -0,0 +1,25 @@
+name: 'Lock Threads'
+
+on:
+  schedule:
+    # This runs every hour: https://crontab.guru/every-1-hour
+    - cron: '0 * * * *'
+  workflow_dispatch:
+
+permissions:
+  issues: write
+  pull-requests: write
+
+concurrency:
+  group: lock
+
+jobs:
+  action:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: dessant/lock-threads@v3
+        with:
+          github-token: ${{ secrets.LOCK_TOKEN }}
+          issue-inactive-days: 30
+          issue-comment: 'This issue has been automatically locked due to no recent activity. If you are running into a similar issue, please create a new issue with the steps to reproduce. Thank you.'
+          pr-inactive-days: 30
diff --git a/.github/workflows/stale.yml b/.github/workflows/stale.yml
index 4d15b37533f69..1cbbfceb7cc5c 100644
--- a/.github/workflows/stale.yml
+++ b/.github/workflows/stale.yml
@@ -2,7 +2,8 @@ name: 'Stale issue handler'
 on:
   workflow_dispatch:
   schedule:
-    - cron: '0 0 * * *'
+    # This runs every day 20 minutes before midnight: https://crontab.guru/#40_23_*_*_*
+    - cron: '40 23 * * *'
 
 jobs:
   stale:
@@ -12,6 +13,7 @@ jobs:
         id: stale
         name: 'Close stale issues with no reproduction'
         with:
+          repo-token: ${{ secrets.STALE_TOKEN }}
           only-labels: 'please add a complete reproduction'
           close-issue-message: 'This issue has been automatically closed after 30 days of inactivity with no reproduction. If you are running into a similar issue, please open a new issue with a reproduction. Thank you.'
           days-before-issue-close: 1
@@ -19,3 +21,4 @@ jobs:
           days-before-pr-close: -1
           days-before-pr-stale: -1
           exempt-issue-labels: 'blocked,must,should,keep'
+          operation-per-run: 300 # 1 operation per 100 issues, the rest is to label/comment/close
diff --git a/docs/basic-features/data-fetching/get-server-side-props.md b/docs/basic-features/data-fetching/get-server-side-props.md
index da2f5e39aae89..22aa4d77dbf73 100644
--- a/docs/basic-features/data-fetching/get-server-side-props.md
+++ b/docs/basic-features/data-fetching/get-server-side-props.md
@@ -33,7 +33,7 @@ The [`getServerSideProps` API reference](/docs/api-reference/data-fetching/get-s
 
 ## When should I use getServerSideProps
 
-You should use `getServerSideProps` only if you need to pre-render a page whose data must be fetched at request time. [Time to First Byte (TTFB)](/learn/seo/web-performance) will be higher than [`getStaticProps`](/docs/basic-features/data-fetching/get-static-props.md) because the server must compute the result on every request, and the result can only be cached by a CDN using `cache-control` headers (which could require extra configuration).
+You should use `getServerSideProps` only if you need to pre-render a page whose data must be fetched at request time. [Time to First Byte (TTFB)](https://web.dev/ttfb/) will be higher than [`getStaticProps`](/docs/basic-features/data-fetching/get-static-props.md) because the server must compute the result on every request, and the result can only be cached by a CDN using `cache-control` headers (which could require extra configuration).
 
 If you do not need to pre-render the data, then you should consider fetching data on the [client side](#fetching-data-on-the-client-side).
 
diff --git a/lerna.json b/lerna.json
index b17ed878a3fb8..3fbc8625cdba1 100644
--- a/lerna.json
+++ b/lerna.json
@@ -16,5 +16,5 @@
       "registry": "https://registry.npmjs.org/"
     }
   },
-  "version": "12.0.9-canary.12"
+  "version": "12.0.9"
 }
diff --git a/packages/create-next-app/package.json b/packages/create-next-app/package.json
index 7204f3e078f19..96b77e4e77616 100644
--- a/packages/create-next-app/package.json
+++ b/packages/create-next-app/package.json
@@ -1,6 +1,6 @@
 {
   "name": "create-next-app",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "keywords": [
     "react",
     "next",
diff --git a/packages/eslint-config-next/package.json b/packages/eslint-config-next/package.json
index 8315f8aabadac..505f4628c3c33 100644
--- a/packages/eslint-config-next/package.json
+++ b/packages/eslint-config-next/package.json
@@ -1,6 +1,6 @@
 {
   "name": "eslint-config-next",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "description": "ESLint configuration used by NextJS.",
   "main": "index.js",
   "license": "MIT",
@@ -9,7 +9,7 @@
     "directory": "packages/eslint-config-next"
   },
   "dependencies": {
-    "@next/eslint-plugin-next": "12.0.9-canary.12",
+    "@next/eslint-plugin-next": "12.0.9",
     "@rushstack/eslint-patch": "^1.0.8",
     "@typescript-eslint/parser": "^5.0.0",
     "eslint-import-resolver-node": "^0.3.4",
diff --git a/packages/eslint-plugin-next/package.json b/packages/eslint-plugin-next/package.json
index 9405a87b6b493..d902660f367b6 100644
--- a/packages/eslint-plugin-next/package.json
+++ b/packages/eslint-plugin-next/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/eslint-plugin-next",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "description": "ESLint plugin for NextJS.",
   "main": "lib/index.js",
   "license": "MIT",
diff --git a/packages/next-bundle-analyzer/package.json b/packages/next-bundle-analyzer/package.json
index 982bddb7c8c24..185a79d13f80e 100644
--- a/packages/next-bundle-analyzer/package.json
+++ b/packages/next-bundle-analyzer/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/bundle-analyzer",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "main": "index.js",
   "license": "MIT",
   "repository": {
diff --git a/packages/next-codemod/package.json b/packages/next-codemod/package.json
index 0cc2279928273..878fa830ed5ef 100644
--- a/packages/next-codemod/package.json
+++ b/packages/next-codemod/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/codemod",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "license": "MIT",
   "dependencies": {
     "chalk": "4.1.0",
diff --git a/packages/next-env/package.json b/packages/next-env/package.json
index 375d55e508fcb..5617323e10e0f 100644
--- a/packages/next-env/package.json
+++ b/packages/next-env/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/env",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "keywords": [
     "react",
     "next",
diff --git a/packages/next-mdx/package.json b/packages/next-mdx/package.json
index 397d93685e047..def2ec94e6824 100644
--- a/packages/next-mdx/package.json
+++ b/packages/next-mdx/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/mdx",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "main": "index.js",
   "license": "MIT",
   "repository": {
diff --git a/packages/next-plugin-storybook/package.json b/packages/next-plugin-storybook/package.json
index 2a1cce549cfba..3b7791aa611f5 100644
--- a/packages/next-plugin-storybook/package.json
+++ b/packages/next-plugin-storybook/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/plugin-storybook",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "repository": {
     "url": "vercel/next.js",
     "directory": "packages/next-plugin-storybook"
diff --git a/packages/next-polyfill-module/package.json b/packages/next-polyfill-module/package.json
index 4760c3bf9871e..b1bf84d56f61e 100644
--- a/packages/next-polyfill-module/package.json
+++ b/packages/next-polyfill-module/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/polyfill-module",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "description": "A standard library polyfill for ES Modules supporting browsers (Edge 16+, Firefox 60+, Chrome 61+, Safari 10.1+)",
   "main": "dist/polyfill-module.js",
   "license": "MIT",
diff --git a/packages/next-polyfill-nomodule/package.json b/packages/next-polyfill-nomodule/package.json
index ea1a5bf15c5d9..1f3736c96b786 100644
--- a/packages/next-polyfill-nomodule/package.json
+++ b/packages/next-polyfill-nomodule/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/polyfill-nomodule",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "description": "A polyfill for non-dead, nomodule browsers.",
   "main": "dist/polyfill-nomodule.js",
   "license": "MIT",
diff --git a/packages/next-swc/package.json b/packages/next-swc/package.json
index b397a17eeb02b..be84cbfa3e27b 100644
--- a/packages/next-swc/package.json
+++ b/packages/next-swc/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/swc",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "private": true,
   "scripts": {
     "build-native": "napi build --platform --cargo-name next_swc_napi native",
diff --git a/packages/next/package.json b/packages/next/package.json
index d66936dad338f..acd0260841b02 100644
--- a/packages/next/package.json
+++ b/packages/next/package.json
@@ -1,6 +1,6 @@
 {
   "name": "next",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "description": "The React Framework",
   "main": "./dist/server/next.js",
   "license": "MIT",
@@ -71,7 +71,7 @@
     ]
   },
   "dependencies": {
-    "@next/env": "12.0.9-canary.12",
+    "@next/env": "12.0.9",
     "caniuse-lite": "^1.0.30001283",
     "postcss": "8.4.5",
     "styled-jsx": "5.0.0",
@@ -119,11 +119,11 @@
     "@hapi/accept": "5.0.2",
     "@napi-rs/cli": "1.2.1",
     "@napi-rs/triples": "1.0.3",
-    "@next/polyfill-module": "12.0.9-canary.12",
-    "@next/polyfill-nomodule": "12.0.9-canary.12",
-    "@next/react-dev-overlay": "12.0.9-canary.12",
-    "@next/react-refresh-utils": "12.0.9-canary.12",
-    "@next/swc": "12.0.9-canary.12",
+    "@next/polyfill-module": "12.0.9",
+    "@next/polyfill-nomodule": "12.0.9",
+    "@next/react-dev-overlay": "12.0.9",
+    "@next/react-refresh-utils": "12.0.9",
+    "@next/swc": "12.0.9",
     "@peculiar/webcrypto": "1.1.7",
     "@taskr/clear": "1.1.0",
     "@taskr/esnext": "1.1.0",
diff --git a/packages/next/server/image-optimizer.ts b/packages/next/server/image-optimizer.ts
index de5a631573130..7a0f7fe1ec180 100644
--- a/packages/next/server/image-optimizer.ts
+++ b/packages/next/server/image-optimizer.ts
@@ -253,8 +253,17 @@ export async function imageOptimizer(
         mockRes.write = (chunk: Buffer | string) => {
           resBuffers.push(Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk))
         }
-        mockRes._write = (chunk: Buffer | string) => {
+        mockRes._write = (
+          chunk: Buffer | string,
+          _encoding: string,
+          callback: () => void
+        ) => {
           mockRes.write(chunk)
+          // According to Node.js documentation, the callback MUST be invoked to signal that
+          // the write completed successfully. If this callback is not invoked, the 'finish' event
+          // will not be emitted.
+          // https://nodejs.org/docs/latest-v16.x/api/stream.html#writable_writechunk-encoding-callback
+          callback()
         }
 
         const mockHeaders: Record<string, string | string[]> = {}
@@ -290,7 +299,6 @@ export async function imageOptimizer(
         await handleRequest(mockReq, mockRes, nodeUrl.parse(href, true))
         await isStreamFinished
         res.statusCode = mockRes.statusCode
-
         upstreamBuffer = Buffer.concat(resBuffers)
         upstreamType =
           detectContentType(upstreamBuffer) || mockRes.getHeader('Content-Type')
@@ -328,7 +336,6 @@ export async function imageOptimizer(
         )
         return { finished: true }
       }
-
       if (!upstreamType.startsWith('image/')) {
         res.statusCode = 400
         res.end("The requested resource isn't a valid image.")
diff --git a/packages/react-dev-overlay/package.json b/packages/react-dev-overlay/package.json
index 8cda508cce57a..a8a7000224e7f 100644
--- a/packages/react-dev-overlay/package.json
+++ b/packages/react-dev-overlay/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/react-dev-overlay",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "description": "A development-only overlay for developing React applications.",
   "repository": {
     "url": "vercel/next.js",
diff --git a/packages/react-refresh-utils/package.json b/packages/react-refresh-utils/package.json
index 8ea294f3ba9e8..66c4a46dcbd41 100644
--- a/packages/react-refresh-utils/package.json
+++ b/packages/react-refresh-utils/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@next/react-refresh-utils",
-  "version": "12.0.9-canary.12",
+  "version": "12.0.9",
   "description": "An experimental package providing utilities for React Refresh.",
   "repository": {
     "url": "vercel/next.js",
diff --git a/test/integration/image-optimizer/test/index.test.js b/test/integration/image-optimizer/test/index.test.js
index 89f9cd36d7fff..26ea2bfc9d3a4 100644
--- a/test/integration/image-optimizer/test/index.test.js
+++ b/test/integration/image-optimizer/test/index.test.js
@@ -779,6 +779,14 @@ function runTests({
     expect(await res.text()).toBe("The requested resource isn't a valid image.")
   })
 
+  it('should error if the image file does not exist', async () => {
+    const query = { url: '/does_not_exist.jpg', w, q: 80 }
+    const opts = { headers: { accept: 'image/webp' } }
+    const res = await fetchViaHTTP(appPort, '/_next/image', query, opts)
+    expect(res.status).toBe(400)
+    expect(await res.text()).toBe("The requested resource isn't a valid image.")
+  })
+
   it('should handle concurrent requests', async () => {
     await fs.remove(imagesDir)
     const query = { url: '/test.png', w, q: 80 }