.net standard 2.0 not supported by 2018?

Hello,

Installed today new 2018.1 beta, but when I will go to player setting I can’t select Scripting Runtime version to use .net standard 2.0 as there is no info about it anywhere.

How I can use it on mac for ios and android platforms?

Thanks

set scripting runtime to 4.6, then api compatibility level to .net standard