MIDI Editor freeze problem

Hi, I upgrade Cubase from 10.0 to 10.5 and I’m struggling with Midi Editor which freezes each time it’s been opened. Frustrating … Any suggestions ? Editor in Lower zone works fine …

iMAC late 2013, 3.5 GHz Intel Core i7, 32 GB 1600 DDR3, NVIDIA GeForce GTX 780M 4 GB


Am I right, you are opening Key Editor in own window, then Cubase freezes?

Is it reproducible in every project? Could you share a project, please? Could you try in Cubase Safe Start mode, please?