Ok, found a sneaky workaround. If the handle can't be made invisible right now, make it small enough that it's hard to click, lol.
Code:
AttachGUIResize(new IPlugGUIResize(this, pGraphics, false, 0, 0));
And stretched out into the full thing, I have this:
Code:
#ifdef __APPLE__
#ifdef VST_API
AttachGUIResize(new IPlugGUIResize(this, pGraphics, false, 0, 0));
#else
AttachGUIResize(new IPlugGUIResize(this, pGraphics, true, 16, 16));
#endif
#else
AttachGUIResize(new IPlugGUIResize(this, pGraphics, true, 16, 16));
#endif