Layer: data not visible

When I apply the layers 'DOV boringen' and 'DOV sonderingen' and click on the data points no data is made visible. See pic:

[byrman]

This has to do with this commit:

https://github.com/nens/lizard-nxt/commit/24d61ef1dbe3b040876b5fb300af9645e666e1d8

GeoServer benaderen via "https://api.ddsc.nl/proxy/?url=..." lukt enkel met http en niet met https.