Export again to see did something gone wrong in the exportation step = fail Uninstall 4.4.1 and tried to Load my Body1.stl in 4.3.0 = fail Uninstall 4.3.0 and tried to Load my Body1.stl in 4.2.x = ...
Open UltiMaker Cura 5.10.1 Open file test-cube1.stl it takes about 100s to get visible to the 3d view. Open file test-cube2.stl it takes less than 1s to get visible to the 3d view. or: Open UltiMaker ...