Running into the same issue myself.
I’ve tried it with the embedded URL listed in the security box, with simply the domain embedded in the security box and with no URL within the security box.
Am wondering if there is something within the 4.2 update that is interfering? Am digging into it, as we’re using your plugin to pull some content from our group wiki to the public-facing pages. It’s a nice tool for minimizing maintenance.
An example of the problem is our front-facing page at https://www.redmountainmakers.org/faq/, which is pulling content from https://wiki.redmountainmakers.org/wiki/FAQ
We haven’t moved over to a signed certificate for our domains – we were waiting to do that as part of a hosting move to be done later this month.