JavaScript EventSource SSE not firing in browser

cracked it! 🙂

Thanks to some help from Tom Kersten who helped me with testing. Turns out the code isnt the problem.

Be warned.. if your client uses any kind of anti-virus software which intercepts web requests, it may cause problems here. In this case, Sophos Endpoint Security, which provides enterprise grade anti-virus and firewall protection has a feature called web protection. Within this features is an option to scan downloads; it seems that the SSE connection is treated as a download and thus not released to the browser until the connection is closed and the stream received to scan. Disabling this option cures the problem. I have submitted a bug report but other anti-virus systems may do the same.

thanks for your suggestions and help everyone 🙂

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