To export as WebM in Blender 2.8 When trying to export an animation into webM i get this error 

I can't find any information about it, what is CQ level?

Important: I am not interested into exporting into frames and using other programs to convert into video ,the programms never works,i lost already too much time and money trying " this one really, it works i swear ".Once again ,not interested.
CQ means constant quality, it has nothing to do with Blender, everything to do with FFmpeg which blender uses for encoding.

https://trac.ffmpeg.org/wiki/Encode/VP9

Try to use WEBM/VP9 as codec with the WEBM container. (output properties, video panel)

Depending on the platform you are working on, it should normally work right out the box.