diff --git a/src/content/reference/react-dom/preinitModule.md b/src/content/reference/react-dom/preinitModule.md
index 97bb4dbc728..35bd0a8a777 100644
--- a/src/content/reference/react-dom/preinitModule.md
+++ b/src/content/reference/react-dom/preinitModule.md
@@ -47,7 +47,7 @@ The `preinitModule` function provides the browser with a hint that it should sta
 * `href`: a string. The URL of the module you want to download and execute.
 * `options`: an object. It contains the following properties:
   *  `as`: a required string. It must be `'script'`.
-  *  `crossOrigin`: a string. The [CORS policy](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/crossorigin) to use. Its possible values are `anonymous` and `use-credentials`.
+  *  `crossOrigin`: a string. The [CORS policy](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/crossorigin) to use. Its possible values are `anonymous` and `use-credentials`. It is required when `as` is set to `"fetch"`.
   *  `integrity`: a string. A cryptographic hash of the module, to [verify its authenticity](https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity).
   *  `nonce`: a string. A cryptographic [nonce to allow the module](https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/nonce) when using a strict Content Security Policy. 
 
diff --git a/src/content/reference/react-dom/preloadModule.md b/src/content/reference/react-dom/preloadModule.md
index ebc2fa6d051..b5d866230bc 100644
--- a/src/content/reference/react-dom/preloadModule.md
+++ b/src/content/reference/react-dom/preloadModule.md
@@ -47,7 +47,7 @@ The `preloadModule` function provides the browser with a hint that it should sta
 * `href`: a string. The URL of the module you want to download.
 * `options`: an object. It contains the following properties:
   *  `as`: a required string. It must be `'script'`.
-  *  `crossOrigin`: a string. The [CORS policy](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/crossorigin) to use. Its possible values are `anonymous` and `use-credentials`.
+  *  `crossOrigin`: a string. The [CORS policy](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/crossorigin) to use. Its possible values are `anonymous` and `use-credentials`. It is required when `as` is set to `"fetch"`.
   *  `integrity`: a string. A cryptographic hash of the module, to [verify its authenticity](https://developer.mozilla.org/en-US/docs/Web/Security/Subresource_Integrity).
   *  `nonce`: a string. A cryptographic [nonce to allow the module](https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/nonce) when using a strict Content Security Policy.