When using a single FBX with multiple meshes that is imported as individual meshes, if you reimport after updating only a single mesh or a few of them the entirety of FBX will be imported and added to this single imported mesh.
This is a regression of behavior from 4.13 that is now broken in 4.14 and 4.15.
Working: 4.13 Binary CL-3172292
Broken: 4.14 Binary CL-3195953
Broken: 4.15 Dev-Rendering CL-3201999
1. Import any FBX asset with multiple meshes
2. In the Import options uncheck "Combine Meshes"
3. Change one of meshes in a modeling program.
4. In the content browser select only the mesh that was changed and right-click > Reimport
Results: When using reimport for a single mesh that was imported with an FBX that contained multiple meshes all the meshes will be imported to this single mesh.
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