AssetBundle Manager crash in WebGL

Hi! Not sure if I should have posted this issue here or in the WebGL forum but here goes -

I'm using the asset bundle manager on WebGL. If I run the build using either "full" exceptions or "explicitly thrown exceptions only", everything works fine and no exceptions appear in the log.

However, if I run the build with "None" exceptions I get an exception on the following, fairly innocent-seeming line.

download = new WWW(url);

As it's downloading the manifest, the url is simply the path to my streamingAssets directory. I can't think of any reason why this line would blow up when no exceptions enabled but function perfectly (levels load correctly) with exceptions on.

I'm using Unity 2017.2.1

Oddly, I used the asset bundle manager with Web GL on Unity 5.6.3 on another project and it worked fine.

Note that I had to modify the AssetBundleManamger.cs slightly to get it to compile on 2017 but this was mainly just removing the lines which referenced the webplayer.

Has anyone else had the same problem and does anyone have any solutions / workarounds? For now I'm just building with "explicitly thrown exceptions only" which isn't optimal.

- Jason