Advanced iframe pro does also support existing resizer scripts that do send the height of the iframe to the parent.
As an enhanced example I have added a demo of the iframe sizer script of https://github.com/davidjbradshaw/iframe-resizer. The demo does initialize the external script and also converts the data received to the internal data structure. You can use the debug mode of advanced iframe to see the incoming message and then you need to use and adopt the example converter script.
You can see the working example including all needed scripts here: https://www.tinywebgallery.com/blog/advanced-iframe/advanced-iframe-pro-demo/integrate-iframe-sizer-script.
Have fun using this new feature. It can already be used with the current version (7.5.7) of advanced iframe pro.
Best, Michael