can't convert ml-agents project to webgl

I have tried several times to convert my project to webgl, but I can't build it. I get 138 errors such as
Assets\ML-Agents\Scripts\DemonstrationStore.cs(3,7): error CS0246: The type or namespace name 'Google' could not be found (are you missing a using directive or an assembly reference?

I tried making an empty new game (with just a cube) and saved it as webgl and that did work

also downloaded UnitySetup-WebGL-Support-for-Editor-2019.3.5f1 seperately and installed that
I am using Unity 2019.3.5f1 and ml-agents-0.13.1
The pc-build is working fine.

 

Solved
upgrade Barracuda a later or latest version (0.61) and change a few lines of script as indicated in following thread if you use ml-agents 0.13.1
https://github.com/Unity-Technologies/ml-agents/commit/584438a7752e874f2b5ab12cb3a5f3fd12533815