docs(pools): clarify profile updates do not propagate to idle pool browsers

Author: masnwilliams

browsers/pools/faq.mdx

@@ -24,6 +24,12 @@ When a browser from a pool is set to be destroyed (by reaching its specified `ti
 
 Yes, use `kernel.browserPools.update()`. By default, idle browsers are discarded and rebuilt with new configuration. Set `discard_all_idle: false` to only apply changes to newly created browsers.
 
+### If I update a profile's contents, will my pool's idle browsers pick up the change?
+
+No. Idle browsers in a pool are pre-loaded with the profile's contents at the time they were filled. Updating the profile (for example, re-saving auth state to the same `profile_id`) does not propagate to already-warmed browsers — only newly-filled browsers will use the updated profile.
+
+To force the pool to pick up new profile contents, either call `kernel.browserPools.flush()` to destroy idle browsers (the pool refills automatically), or call `kernel.browserPools.update()` with `discard_all_idle: true`.
+
 ### Should I set `reuse: true` or `reuse: false` when releasing?
 
 Use `reuse: true` (default) for efficiency. Only use `reuse: false` when you suspect browser state corruption or need a guaranteed clean browser session.