Better messaging on nodejs_compat within Vitest Pool Workers

Author: andyjessop

src/content/docs/workers/testing/vitest-integration/isolation-and-concurrency.mdx

@@ -56,12 +56,12 @@ In this model, a single `workerd` process is started with a single Worker for al
 
 Each Worker has its own module cache. As Workers are reused between test runs, their module caches are also reused. Vitest invalidates parts of the module cache at the start of each test run based on changed files.
 
-The Workers Vitest pool works by running code inside a Cloudflare Worker that Vitest would usually run inside a [Node.js worker thread](https://nodejs.org/api/worker_threads.html). To make this possible, the pool requires the [`nodejs_compat`](/workers/configuration/compatibility-flags/#nodejs-compatibility-flag) and [`export_commonjs_default`](/workers/configuration/compatibility-flags/#commonjs-modules-do-not-export-a-module-namespace) compatibility flags to be enabled. The pool also configures `workerd` to use Node-style module resolution and polyfills required `node:*` modules not provided by `nodejs_compat`.
+The Workers Vitest pool works by running code inside a Cloudflare Worker that Vitest would usually run inside a [Node.js worker thread](https://nodejs.org/api/worker_threads.html). To make this possible, the pool **automatically injects** the [`nodejs_compat`](/workers/configuration/compatibility-flags/#nodejs-compatibility-flag) and [`export_commonjs_default`](/workers/configuration/compatibility-flags/#commonjs-modules-do-not-export-a-module-namespace) compatibility flags to be enabled. The pool also configures `workerd` to use Node-style module resolution and polyfills required `node:*` modules not provided by `nodejs_compat`.
 
 :::caution
 
 
-Using the pool may cause your Worker to behave differently when deployed than during testing, as Node-style resolution and additional polyfills will be available to your Worker's source code and dependencies too.
+Using Vitest Pool Workers may cause your Worker to behave differently when deployed than during testing as the `nodejs_compat` flag is enabled by default. This means that Node.js-specific APIs and modules are available when running your tests. However, Cloudflare Workers do not support these Node.js APIs in the production environment unless you specify this flag in your Worker configuration.
 
 
 :::