IW iw15.5.6 - nonSSL lock message when starting app as exe

I will go back to 15.5.5 to check,
Here is the message I get, but the application still works for HTTP:
"SSLOptions.NonSSLRequest(is locked. Suggestion: Set in ServerController OnConfig event instead."

I CAN SEE it did not get this error in 15.4.1

Please advise
TIA

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IW 15.5.5 shows same error message...