diff --git a/docs/src/test-configuration-js.md b/docs/src/test-configuration-js.md
index 822bd4ea0d..4c0c9e90e2 100644
--- a/docs/src/test-configuration-js.md
+++ b/docs/src/test-configuration-js.md
@@ -68,6 +68,10 @@ export default defineConfig({
 | [`property: TestConfig.webServer`] | To launch a server during the tests, use the `webServer` option |
 | [`property: TestConfig.workers`] | The maximum number of concurrent worker processes to use for parallelizing tests. Can also be set as percentage of logical CPU cores, e.g. `'50%'.`. See [Parallelism](./test-parallel) and [Sharding](./test-sharding) for more details. |
 
+:::warning
+Playwright executes the configuration file multiple times. Do not dynamically produce non-stable values in your configuration (for example, using the current datetime in [`property: TestProject.name`]).
+:::
+
 ## Filtering Tests
 
 Filter tests by glob patterns or regular expressions.