Troubleshooting Guide

If you cannot see thumbnails or previews for 3MF, GLB, or G-code files after installing MakersPreview, please try the following steps.

1 Enable Application Extensions

First, launch the MakersPreview application, as it typically registers its plugins automatically. If the extensions are still missing, go to System Settings > Extensions > Added Extensions and ensure both MakersPreview modules are enabled. We recommend restarting your system afterwards to confirm the changes.

2 Reset QuickLook Cache

Sometimes the macOS cache prevents newly installed previewers from taking effect specifically for thumbnails. Open Terminal, copy and run the following command:

qlmanage -r && qlmanage -r cache && killall Finder

Note: This step is specifically for resolving issues where 3D thumbnails (3MF, GLB, etc.) are not appearing correctly in Finder. After running it, check the folders that previously failed to show thumbnails.

3 Check System UTI Recognition

If resetting the cache doesn't work, there might be a conflict in how the system identifies file types (UTI). Run this in Terminal:

mdls -name kMDItemContentType [Drag your 3MF/GLB file here]

How to: Type mdls -name kMDItemContentType (with a space at the end), then drag any 3MF or GLB file from Finder into the Terminal window and press Enter.

Check the returned value and send the result to our email: whimwild.com@gmail.com