Difference with .refresh between 2018 r3 and r4

Bonjour,

With 2018 R4, canvas.refresh is not updating instantly the canvas under Mojave as do R3.
Is that a bug? known?

Thanks

  1. we are advised to use .invalidate instead of refresh
  2. I have noticed no difference in m projects with 2018.4
    Do you have code to recreate what you are seeing?