Custom asset URL cleanup

Author: AugustMiller

docs/cloud/assets.md

@@ -146,13 +146,17 @@ The Cloud extension will construct predictable production URLs for _existing_ as
 You can configure a custom [rewrite](redirects.md#rewrites) to serve assets from additional URLs or paths.
 However, Craft will continue to generate canonical CDN URLs, unless you explicitly set a **Base URL** in the filesystem’s settings.
 
+::: danger
+Misconfiguration of the **Base URL** setting can result in Craft generating incorrect or invalid asset URLs.
+:::
+
 In most cases, this should point to an [environment variable](environments.md#variables) containing a fully-qualified URL—likely one of your configured [domains](domains.md).
 
 ::: warning
 Using a value beginning with `@web` is strongly discouraged, as its value can differ based on how the site is accessed.
 :::
 
-To serve assets from a vanity domain like `assets.mydomain.com`, follow these steps:
+To serve assets from a vanity domain like `cdn.mydomain.com`, follow these steps:
 
 1. Create a [subdomain](domains.md#subdomains);
 1. Add a rewrite to your `cloud.yaml` file:
@@ -167,5 +171,6 @@ To serve assets from a vanity domain like `assets.mydomain.com`, follow these st
     ```
 1. Define a variable containing that domain in each of your environments, like `ASSET_DOMAIN_HOST`;
 1. Set **Base URL** in your Cloud filesystem to `$ASSET_DOMAIN_HOST/assets/`;
+1. Commit the resulting project config changes and [deploy](deployment.md) your environment;
 
-If you are not using a **Subpath**, you can omit that from the **Base URL** setting.
+If you are not using a **Subpath**, omit that segment from the `pathname` and  **Base URL** settings.

docs/cloud/redirects.md

@@ -117,7 +117,7 @@ rewrites:
     destination: '{assetBaseUrl}/{matches.pathname.groups.assetPath}{request.url.search}'
 ```
 
-With this strategy, your files are still stored on (and available from) our CDN—all we’ve done is create an alias for the canonical CDN URL. _Craft continues to generate canonical URLs for assets to ensure that they resolve, independent of rewrite configuration._
+With this strategy, your files are still stored on (and available from) our CDN—all we’ve done is create an alias for the canonical CDN URL. Craft continues to generate canonical URLs for assets to ensure that they resolve, independent of rewrite configuration, unless you [explicitly set a custom URL](assets.md#custom-urls).
 
 [Build artifacts](/knowledge-base/cloud-builds) (including static files from your web root) can also be proxied: