Add a hint for the readers with a suggested workaround #4463
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...for a described limitation.
In this PR, I suggest including a hint for the readers of the book to clarify how they can observe the behavior described in the multi-threaded web server section. Due to certain browser-specific limitations (such as request caching or connection reuse within the same browser), the non-blocking handling of concurrent requests may not be evident when using a single browser.
The added note suggests using either multiple different browsers or a tool like
curlto simulate multiple simultaneous requests more effectively, helping readers better understand and verify the server’s concurrent behavior as intended.