Clipping Plane Glitch?

I’ve just started using Rhino 6 and every time I create a clipping plane, I get a weird glitch (see attached photo)

This happens in both wireframe and shaded display modes (but not in render)

Hi - we recently fixed an issue on the Mac that looked like that.
Please run the Rhino SystemInfo command and copy-paste the result in an answer here.

Rhino 6 SR18 2019-9-23 (Public Build, 6.18.19266.13352, Git hash:master @ 3d84f88dec99b2f4e8b7497e739ed2adc2ba8ef6)
License type: Evaluation, build 2019-09-23
License details: Stand-Alone
Expires on: 2020-04-26

Apple Intel 64-bit macOS Version 10.14.3 (Build 18D42) (Physical RAM: 8Gb)
Mac Model Identifier: MacBookPro9,2
Machine name: MacBook Pro
Language: en-GB (MacOS default)

Intel HD Graphics 4000 OpenGL Engine (OpenGL ver:4.1 INTEL-12.4.7)

OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
Redraw scene when viewports are exposed: On

Anti-alias mode: 4x
Mip Map Filtering: Linear
Anisotropic Filtering Mode: Height

Vendor Name: Intel Inc.
Render version: 4.1
Shading Language: 4.10
Maximum Texture size: 16384 x 16384
Z-Buffer depth: 24 bits
Maximum Viewport size: 16384 x 16384
Total Video Memory: 1536 MB
Graphics: Intel HD Graphics 4000
Displays: HP 23xi (96dpi 1x), Color LCD (114dpi 1x)

Graphics processors
Intel HD Graphics 4000 (1536 MB)
Color LCD (1280 x 800)
HP 23xi (1920 x 1080 @ 60 Hz)

USB devices
Apple Inc.: FaceTime HD Camera (Built-in)
Apple Inc.: Apple Internal Keyboard / Trackpad
Apple Computer, Inc.: IR Receiver
Apple Inc.: Bluetooth USB Host Controller
MOSART Semi.: 2.4G Wireless Mouse
3Dconnexion: SpaceMouse Compact

Bluetooth devices
Apple: Apple Wireless Keyboard
Apple: Apple Wireless Trackpad

Third party kernel extensions
com.3dconnexion.driver (1.1.0) 94E8C49C-EDED-3526-88BE-E7207560C0D2

Third party plugins

Rhino plugins
/Applications/ “RhinoCycles” 6.18.19266.13352
/Applications/ “Snapshots” 6.18.19266.1002
/Applications/ “Grasshopper” 6.18.19266.13352
/Applications/ “PanelingTools” 6.18.19266.1002
/Users/oscarallan/Library/Application Support/McNeel/Rhinoceros/MacPlugIns/MaideRhinoPlugin.rhp “MaideRhinoPlugin”
/Applications/ “Commands” 6.18.19266.13352
/Applications/ “RDK_EtoUI” 6.18.19266.13352
/Applications/ “Displacement” 6.18.19266.1002
/Applications/ “IronPython” 6.18.19266.13352
/Applications/ “Rhino Render” 6.18.19266.1002
/Applications/ “AnimationTools” 6.18.19266.1002
/Applications/ “Renderer Development Kit” 6.18.19266.1002

Hi - the fix that I mentioned is in 6.23.
You can download the SR Candidate from this link: