Anyone? No one at all?
I am experiencing the same issue and could not find a solution until now.
I've decided to give up on WebDirect, it is extremely slow on internet, keep freshing on certain machines and the container field is simply not working.
I will switch my solution back to supercontainer and PHP.
glad at least someone reported the same issue as myself. I kept reading in FM documentation that containers work fine with WebDirect but this is certainly not the case!
I did however found a very simple solution. Since the client only wanted to show PDFs, I used instead a web viewer by adding the following code:
"data:application/pdf;base64," & Base64Encode ( [your container field])
You should however check that the file is a PDF first.
I do concur to your conclusion that WebDirect is still rubbish and I was really hoping for FM to fix more stuff and even add a few new features as many people think they just launched it pre-maturely. Instead they make take Apple approach of putting much needed features in the newer version !!