feat: release 6.4.0 (#789)

Co-authored-by: webiny-bot <webiny-bot@webiny.com>
Co-authored-by: adrians5j <adrian@webiny.com>
Co-authored-by: Pavel Denisjuk <pavel@webiny.com>

Author: 4 people

AGENTS.md

@@ -15,6 +15,11 @@ When editing a generated `changelog.mdx` file, always keep the sibling `changelo
 - **Removed entry** → add the PR number(s) to the `## Skipped PRs` section with a short reason
 - **Rewritten entry** → add a note to the `## Manual Rewrites` section
 
+**Writing style for changelog entries:**
+
+- Keep entries user-facing — describe the impact for the user, not internal implementation details (e.g. "X wasn't cached, slowing down the API" rather than "X was fetched outside the cache boundary")
+- Entry descriptions should be 1-2 sentences. Bullet lists for key changes only when there are multiple distinct sub-items.
+
 The `generate-changelog.ts` script reads `## Skipped PRs` to avoid re-adding manually removed entries on the next run. If `changelog.ai.txt` is not updated, removed PRs will reappear.
 
 ### Validation and Quality
@@ -130,6 +135,17 @@ Alert types:
 
 - use <Image/> (src/components/Image.js) component when adding images
 
+#### Video
+
+- use `<Video>` (global MDX component, no import needed) for embedded videos
+- Video files must be **imported** as ESM imports, not referenced by string path:
+
+  ```mdx
+  import myVideo from "./assets/my-video.mp4";
+
+  <Video src={myVideo} controls={true} />
+  ```
+
 ### Code Blocks
 
 - Language tag is always specified: ` ```typescript ` or ` ```graphql `

docs/developer-docs/6.x/admin/assets/file-url-formatter.png

@@ -0,0 +1,84 @@
+---
+id: a3f8kd92
+title: File URL Formatter
+description: Learn how to customize file and image URLs in the Webiny admin app using the FileUrlFormatter extension point.
+---
+
+import { Alert } from "@/components/Alert";
+import fileUrlFormatter from "./assets/file-url-formatter.png";
+
+<Alert type="success" title="WHAT YOU'LL LEARN">
+
+- what the FileUrlFormatter extension point is and where it applies
+- how to implement and register a custom file URL formatter
+- how to remap query parameters for your own CDN or image service
+
+</Alert>
+
+## Overview
+
+<Alert type="info">
+
+This extension point is most relevant if you are replacing Webiny's built-in File Manager with your own Digital Asset Manager (DAM). If you are using the default File Manager, no configuration is needed.
+
+</Alert>
+
+File URLs for images displayed in the Admin app pass through the `FileUrlFormatter` extension point before being rendered.
+
+You can customize how those URLs are constructed: remap parameters to your CDN's own syntax, add authentication tokens, rewrite the host, or apply any other transformation your image delivery pipeline requires. For example, `FilePicker` calls `format(url, { width: 128 })` when rendering thumbnails — a custom formatter can intercept that and swap the standard `?width=N` for whatever your CDN expects.
+
+<Alert type="info">
+
+Only one `FileUrlFormatter` is active at a time. When you register your own implementation it replaces the File Manager default — the last implementation registered wins.
+
+</Alert>
+
+## Implement the Formatter
+
+Create an implementation of `FileUrlFormatter`. The `url` object is mutable — modify it in place. `params.width` is the only supported parameter.
+
+```typescript extensions/fileUrlFormatter/MyFileUrlFormatter.ts
+import { FileUrlFormatter } from "webiny/admin/file-manager";
+
+class MyFileUrlFormatter implements FileUrlFormatter.Interface {
+    format(url: URL, params?: FileUrlFormatter.Params): void {
+        if (params?.width !== undefined) {
+            url.searchParams.set("my_width", String(params.width));
+        }
+    }
+}
+
+export const MyFileUrlFormatterImpl = FileUrlFormatter.createImplementation({
+    implementation: MyFileUrlFormatter,
+    dependencies: []
+});
+```
+
+## Register the Formatter
+
+Wrap the implementation in a feature and mount it with `RegisterFeature`:
+
+```tsx extensions/fileUrlFormatter/index.tsx
+import React from "react";
+import { createFeature, RegisterFeature } from "webiny/admin";
+import { MyFileUrlFormatterImpl } from "./MyFileUrlFormatter.js";
+
+const FileUrlFormatterFeature = createFeature({
+    name: "MyApp/FileUrlFormatter",
+    register(container) {
+        container.register(MyFileUrlFormatterImpl).inSingletonScope();
+    }
+});
+
+export default () => <RegisterFeature feature={FileUrlFormatterFeature} />;
+```
+
+Then add the extension to your `webiny.config.tsx`:
+
+```tsx webiny.config.tsx
+<Admin.Extension src={"@/extensions/fileUrlFormatter/index.tsx"} />
+```
+
+With the extension registered, file thumbnails in the Admin app will use your formatter. Here is the result:
+
+<Image src={fileUrlFormatter} alt="File URL Formatter result" />

docs/developer-docs/6.x/admin/file-url-formatter.mdx

@@ -48,6 +48,7 @@ export const Navigation = ({ children }: { children: React.ReactNode }) => {
         <Page link={"admin/whitelabeling"} />
         <Page link={"admin/connect-custom-domain"} />
         <Page link={"admin/build-params"} />
+        <Page link={"admin/file-url-formatter"} />
       </Group>
       <Group
         title={"API"}
@@ -125,6 +126,7 @@ export const Navigation = ({ children }: { children: React.ReactNode }) => {
           title={"Customize Page List Columns"}
         />
         <Page link={"website-builder/event-handlers"} title={"Event Handlers"} />
+        <Page link={"website-builder/preview-url-modifier"} title={"Preview URL Modifier"} />
       </Group>
       <Group
         title={"Tenant Manager"}

docs/developer-docs/6.x/navigation.tsx

@@ -274,6 +274,19 @@ Adds a fully custom Lambda function to the API application, with both an applica
 | `functionSrc` | `string` | Yes      | Path to the Lambda handler source file                                       |
 | `pulumiSrc`   | `string` | Yes      | Path to the Pulumi infrastructure file (must follow `ApiPulumi` abstraction) |
 
+### Infra.Api.MaxBundleSize
+
+Sets the maximum allowed size of the backend (AWS Lambda) function code. If the built output exceeds this limit, the build fails immediately. The default is **4.5 MB**.
+
+| Prop   | Type     | Required | Description                   |
+| ------ | -------- | -------- | ----------------------------- |
+| `size` | `number` | Yes      | Maximum bundle size in bytes. |
+
+```tsx
+{/* Raise the API bundle size limit to 6 MB */}
+<Infra.Api.MaxBundleSize size={6 * 1024 * 1024} />
+```
+
 ### Infra.Api.StackOutputValue
 
 Adds a custom key-value entry to the API Pulumi stack outputs. Can be used multiple times.

docs/developer-docs/6.x/reference/extensions/infra.mdx

@@ -0,0 +1,109 @@
+---
+id: m4x7pq2n
+title: Preview URL Modifier
+description: Learn how to inject custom query parameters into Website Builder's live preview URLs.
+---
+
+import { Alert } from "@/components/Alert";
+
+<Alert type="success" title="WHAT YOU'LL LEARN">
+
+- what the PreviewUrlModifier extension point is and where it applies
+- how to implement and register a custom preview URL modifier
+- how to use async operations (e.g. fetching a signed token) inside a modifier
+
+</Alert>
+
+## Overview
+
+Every live preview URL that Website Builder generates — in the page editor iframe, the address bar's copy link button, and the pages list — can be customized via the `PreviewUrlModifier` extension point.
+
+When registered, the modifier receives the fully-constructed `URL` object just before it is used. You can add, remove, or change any query parameter, including ones fetched asynchronously from a remote API.
+
+<Alert type="info">
+
+Only one `PreviewUrlModifier` can be registered per project. Avoid setting parameters that start with `wb.` — those are reserved for internal Website Builder use.
+
+</Alert>
+
+## Implement the Modifier
+
+Create a class that implements `PreviewUrlModifier.Interface`. The single required method is `modify(url: URL): Promise<void>`. Mutate the `url` object in place — the return value is ignored.
+
+```typescript extensions/previewUrlModifier/MyPreviewUrlModifier.ts
+import { PreviewUrlModifier } from "webiny/admin/website-builder";
+
+class MyPreviewUrlModifier implements PreviewUrlModifier.Interface {
+  async modify(url: URL) {
+    url.searchParams.set("my-param", "my-value");
+  }
+}
+
+export default PreviewUrlModifier.createImplementation({
+  implementation: MyPreviewUrlModifier,
+  dependencies: []
+});
+```
+
+### Async Example — Fetching a Signed Token
+
+Mark the method `async` to perform any async work before the URL is handed back:
+
+```typescript extensions/previewUrlModifier/MyPreviewUrlModifier.ts
+import { PreviewUrlModifier } from "webiny/admin/website-builder";
+
+class MyPreviewUrlModifier implements PreviewUrlModifier.Interface {
+  async modify(url: URL) {
+    const token = await fetch("/api/preview-token").then(r => r.text());
+    url.searchParams.set("token", token);
+  }
+}
+
+export default PreviewUrlModifier.createImplementation({
+  implementation: MyPreviewUrlModifier,
+  dependencies: []
+});
+```
+
+## Register the Feature
+
+Wire the implementation into the DI container using `createFeature` and `RegisterFeature`:
+
+```tsx extensions/previewUrlModifier/index.tsx
+import React from "react";
+import { createFeature, RegisterFeature } from "webiny/admin";
+import MyPreviewUrlModifier from "./MyPreviewUrlModifier.js";
+
+const PreviewUrlModifierFeature = createFeature({
+  name: "MyApp/PreviewUrlModifier",
+  register(container) {
+    container.register(MyPreviewUrlModifier);
+  }
+});
+
+export default () => <RegisterFeature feature={PreviewUrlModifierFeature} />;
+```
+
+Then register the extension in `webiny.config.tsx`:
+
+```tsx webiny.config.tsx
+import React from "react";
+import { Admin } from "webiny/extensions";
+
+export const Extensions = () => {
+  return (
+    <>
+      {/* ... other extensions */}
+      <Admin.Extension src={"@/extensions/previewUrlModifier/index.tsx"} />
+    </>
+  );
+};
+```
+
+## Where the Modifier Applies
+
+| Surface | Description |
+|---|---|
+| Editor iframe | The live-editing iframe in the page editor |
+| Address bar link | The "copy preview link" button in the editor toolbar |
+| Pages list | Preview icon links in the pages list table |