Rhino 9 WIP Select Color dialog crash (.NET 8)

Running Rhino 9.0.26132.12305 in .NET 8 crashes Rhino silently when user wants to open Select Color dialog. It doesn’t matter how we want to bring it up, Layer Color, Object Color, Material Color it all ends with the same crash. .NET 9 and 10 works ok.

System Info

Rhino 9 SR0 2026-5-12 (Rhino WIP, 9.0.26132.12305, Git hash:master @ e4ca4a25a2667146cdb0b9e48607c637ec745bdb)
License type: Educational, build 2026-05-12
License details: Cloud Zoo
Expires on: 2026-06-26

Windows 11 (10.0.26200 SR0.0) or greater (Physical RAM: 64GB)
.NET 9.0.14

Computer platform: LAPTOP - Plugged in [100% battery remaining]

Non-hybrid graphics configuration using OpenGL
Primary display: NVIDIA RTX A3000 12GB Laptop GPU (NVidia) Memory: 11GB, Driver date: 4-23-2026 (M-D-Y). OpenGL(4.6.0 NVIDIA 596.36)
> Integrated accelerated graphics device with 4 adapter port(s)
- Windows Main Display is laptop’s integrated screen or built-in port
Primary OpenGL: NVIDIA RTX A3000 12GB Laptop GPU (NVidia) Memory: 11GB, Driver date: 4-23-2026 (M-D-Y). OpenGL Ver: 4.6.0 NVIDIA 596.36
> Integrated accelerated graphics device with 4 adapter port(s)
- Windows Main Display is laptop’s integrated screen or built-in port

Secondary graphics devices.
Intel(R) UHD Graphics (Intel) Memory: 2GB, Driver date: 3-3-2026 (M-D-Y).
> Integrated graphics device with 4 adapter port(s)
- There are no monitors attached to this device.

OpenGL Settings
Safe mode: Off
Use accelerated hardware modes: On
GPU Tessellation is: On
Redraw scene when viewports are exposed: On
Graphics level being used: OpenGL 4.6 (primary GPU’s maximum)

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

Vendor Name: NVIDIA Corporation
Render version: 4.6
Shading Language: 4.60 NVIDIA
Driver Date: 4-23-2026
Driver Version: 32.0.15.9636
Maximum Texture size: 32768 x 32768
Z-Buffer depth: 24 bits
Maximum Viewport size: 32768 x 32768
Total Video Memory: 11520 MB

OpenBLAS: OpenBLAS 0.3.30 DYNAMIC_ARCH NO_AFFINITY Haswell MAX_THREADS=64.

Rhino plugins that do not ship with Rhino
C:\ProgramData\McNeel\Rhinoceros\7.0\Plug-ins\Datasmith Rhino Exporter (d1fdc795-b334-4933-b680-088119cdc6bb)\DatasmithRhino7.rhp “Datasmith Exporter” 5.6.1.0
C:\Users\Czaja\source\repos\GH_Controller\GH_Controller\bin\Debug\net7.0\GH_Controller.rhp “GH_Controller” 1.0.0.0
C:\Users\Czaja\AppData\Roaming\McNeel\Rhinoceros\packages\9.0\DynamicEtoPanels\1.0.9\net7.0\DynamicEtoPanels.rhp “DynamicEtoPanels” 1.0.9.0
C:\Users\Czaja\AppData\Roaming\McNeel\Rhinoceros\7.0\Plug-ins\Crayon (39629248-4fa6-47b8-83c7-745a7efea259)\1.2.0.0\Crayon\Crayon.rhp “Crayon” 1.0.0.0
C:\Users\Czaja\AppData\Roaming\McNeel\Rhinoceros\packages\9.0\BlockEditNew\2.1.5\blockeditnew.rhp “BlockEditNew” 2.0.0.0

Rhino plugins that ship with Rhino
C:\Program Files\Rhino 9 WIP\Plug-ins\Commands.rhp “Commands” 9.0.26132.12305
C:\Program Files\Rhino 9 WIP\Plug-ins\rdk.rhp “Renderer Development Kit”
C:\Program Files\Rhino 9 WIP\Plug-ins\UpdatesAndStatistics\UpdatesAndStatistics.rhp “UpdatesAndStatistics” 9.0.26132.12305
C:\Program Files\Rhino 9 WIP\Plug-ins\RhinoRenderCycles.rhp “Rhino Render” 9.0.26132.12305
C:\Program Files\Rhino 9 WIP\Plug-ins\rdk_etoui.rhp “RDK_EtoUI” 9.0.26132.12305
C:\Program Files\Rhino 9 WIP\Plug-ins\NamedSnapshots.rhp “Snapshots”
C:\Program Files\Rhino 9 WIP\Plug-ins\MeshCommands.rhp “MeshCommands” 9.0.26132.12305
C:\Program Files\Rhino 9 WIP\Plug-ins\RhinoCycles.rhp “RhinoCycles” 9.0.26132.12305
C:\Program Files\Rhino 9 WIP\Plug-ins\3dxrhino.rhp “3Dconnexion 3D Mouse”
C:\Program Files\Rhino 9 WIP\Plug-ins\Displacement.rhp “Displacement”
C:\Program Files\Rhino 9 WIP\Plug-ins\SectionTools.rhp “SectionTools”

We are in the process of switching Rhino 9 to be only .NET 10 (or Framework 4.8) for reasons like this. Is there are reason you need to be on .NET 8?

If i remember correctly I was developing some test plugin and for some reason I needed .NET 8. The fact that I don’t even remember exactly what it was means that it might be not that important for me and I will stick with .NET 10.