Hi,
I wanted to try Unity on Linux and I used Playmaker as test asset.
I started with "Get Owner" action on an empty game object. Get Owner has only "Store Game Object" field.
When clicked to Store Game Object, a small menu opens (naturally) to add New Variable or Global Variable. On this small menu, after clicking to New Variable, it does not type. So Variable can not be added. (If it types, I will write a name and save the variable)
But if I change to Variables tab, from there I am able to create new Variable.
In Unity, typing works in everywhere until now, except this issue I noticed, so I wanted to report it. I confirm typing works on Playmaker component in inspector too.
I am using Kubuntu 18.04 (Linux), Unity 2017.4.19 and Playmaker 1.9.0.p6.