I looked in this forum but did not see the fix was already in for LM HF4.
That's because, this time, we released the update before anyone in the forum reported a problem with it.
That's what I meant when I said "each time P3D get a new build, it needs an updated Addon Manager .DLL", so you would know that, as soon as you install a new P3D build, the first thing to do is to reinstall any one FSDT product, since the installer always automatically download the most recent version of the .DLL, which is why we don't always have to announce it.
So, once you know the general rule, first thing to do, is to reinstall any FSDT product, and chances are the .DLL that is downloaded automatically when you run any installer, has already been updated to support any new FSX or P3D build.