With such backends you need to tell the backend that the origin is https, otherwise it will 'think' its serving http since it is unaware of a proxy.

ea.

<!-- This connector is for normal HTTP connections -->
<Connector port="8080" protocol="HTTP/1.1"
proxyPort="443"
proxyName="domain.nl"

You might get away with a static set host value.

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nginx for Windows http://nginx-win.ecsds.eu/