Simulate piston for forklift using PhysX 3.4 ( Unity 2018.3 )

I need to simulate a piston for a forklift, but I don’t really know how to create an accurate physics model.

The forklift ( a car with some wheel colliders ) should react to the force applied by cargo on the forks, but the forks should also move along the lift axis and sideways while colliding with cargo and the environment, and the forklift should react to the changes, if the forks hit a wall, the forklift should react accordingly, and if the forks hit the floor or a ceiling, it should lift itself or push itself away.

Right now I only have a lift that moves the cargo accordingly with credible friction and also reacts to the velocity of the forklift but if I hit the forks against walls or other static colliders, the forks just go through and the forklift doesn’t react at all ( I’m just syncing the forks rigidbody with the movement of the lift using FixedUpdate).

I have tried using different approaches and some physics libraries compatible with Unity ( Newton Dynamics, Bullet ) but yet, none have succeeded.

Webstorm 2018.3 lagging on mac

after update from webstorm 2018.1 to 2018.3 the huge lags appeared. The processor loaded only 10-25%, 2-3gb ram also not used. Why webstorm don’t use more resources if it necessary? My custom VM options…

# custom WebStorm VM options  -Xms1024m -Xmx8192m -XX:MaxPermSize=1024m -XX:ReservedCodeCacheSize=1024m -XX:+UseCompressedOops -Dfile.encoding=UTF-8 -XX:+UseConcMarkSweepGC -XX:SoftRefLRUPolicyMSPerMB=50 -ea -Dsun.io.useCanonCaches=false -Djava.net.preferIPv4Stack=true -XX:+HeapDumpOnOutOfMemoryError -XX:-OmitStackTraceInFastThrow -Xverify:none  -XX:ErrorFile=$  USER_HOME/java_error_in_webstorm_%p.log -XX:HeapDumpPath=$  USER_HOME/java_error_in_webstorm.hprof 

Maybe something wrong in config? mac os version: 10.11.6. I don’t understand why it happening

How do I create an empty Prefab with Unity 2018.3?

I was using Unity 2018.1.(something), where I could simply create an empty Prefab object, then drag a Game Object to the Prefab from the Hierarchy to fill it. When I updated to Unity 2018.3.0f2, I don’t see any more empty Prefab object in the create menu, all I get is Prefab Variant (which is disabled).

I read the Unity Blog talking about new prefab workflows, and I could not find any changes in how Prefabs are created.