What it does
Finder thumbnails
See a useful 3D representation in Finder icon and gallery views.
Interactive Quick Look
Select a 3MF file and press Space to rotate, zoom, and pan the model.
Clear fallbacks
Damaged, oversized, or unsupported files show a readable explanation instead of a blank preview.
Getting started
- Install ThreeMF Preview.
- Open System Settings → General → Login Items & Extensions → Quick Look and enable the ThreeMF Preview extensions.
- Open a folder containing .3mf files in Finder.
- Use Icon or Gallery view to see thumbnails.
- Select a file and press Space to open the interactive Quick Look preview.
Troubleshooting
A thumbnail does not appear
Make sure the file ends in .3mf, the extension is enabled, and Finder has had a moment to generate the preview. Refresh Quick Look with qlmanage -r in Terminal, then relaunch Finder.
Quick Look shows a fallback card
The archive may be damaged, too large, too complex, or use an extension that is not supported yet. The card is intentional: it prevents Finder from hanging while explaining the next step.
How should I report a problem?
Email support@showleafy.com with your macOS version, ThreeMF Preview version, the exact symptom, and whether you can reproduce it. Please do not attach a private model unless you explicitly choose to share it.
Need more help?
We are happy to help you understand what happened and what to try next.
Email support