Playground older versions broken

The playground no longer works when changing the babylonjs version to anything other than latest (4.2 etc), due to:
Uncaught (in promise) TypeError: Cannot read property 'IsSupportedAsync' of undefined

This must be a fairly recent change as it was working a couple of weeks ago when I posted a pg link here.

Hi @sable, pinging @RaananW on this one,

What playground exactly? or the entire playground website?

Ah! Problem found, working on a fix. thanks for reporting!