STEP format not available in Omniverse Isaac Sim CAD importer

Hi @ombudsthom

It seems to be there is a problem with the omni.kit.imported.cad extension in Isaac Sim 2022.1.0 docker version during loading. That is why the red warning symbol. The error comes from the libfontconfig library

2022-08-28 17:01:31 [13,348ms] [Error] [carb] [Plugin: libomni.kit.importer.cad.plugin.so] Could not load the dynamic library from /isaac-sim/exts/omni.kit.importer.cad-0.3.1+lx64.r.cp37/bin/libomni.kit.
importer.cad.plugin.so. Error: libfontconfig.so.1: cannot open shared object file: No such file or directory                                                                                               
2022-08-28 17:01:31 [13,348ms] [Warning] [carb] Potential plugin preload failed: /isaac-sim/exts/omni.kit.importer.cad-0.3.1+lx64.r.cp37/bin/libomni.kit.importer.cad.plugin.so                            
2022-08-28 17:01:31 [13,348ms] [Error] [omni.ext.plugin] [ext: omni.kit.importer.cad-0.3.1] failed to load native plugin: /isaac-sim/exts/omni.kit.importer.cad-0.3.1+lx64.r.cp37/bin/libomni.kit.importer.
cad.plugin.so                                                                                                                                                                                              
2022-08-28 17:01:31 [13,359ms] [Error] [carb.scripting-python.plugin] RuntimeError: Failed to acquire interface: omni::isaac::cad_importer::CadImporter (pluginName: nullptr)                              
                                                                                                                                                                   
At:                                                                                                                                                                                                        
/isaac-sim/exts/omni.kit.importer.cad-0.3.1+lx64.r.cp37/omni/kit/importer/cad/scripts/cad_importer_helper.py(29): __init__                                                                               
/isaac-sim/exts/omni.kit.importer.cad-0.3.1+lx64.r.cp37/omni/kit/importer/cad/scripts/extension.py(46): on_startup                                                                                       
/isaac-sim/kit/plugins/bindings-python/omni/ext/impl/_internal.py(135): _startup_ext                                                                                                                     
/isaac-sim/kit/plugins/bindings-python/carb/profiler/__init__.py(80): wrapper                                                                                                                            
/isaac-sim/kit/plugins/bindings-python/omni/ext/impl/_internal.py(186): startup                                                                                                                          
/isaac-sim/kit/plugins/bindings-python/omni/ext/impl/_internal.py(268): startup_extension                                                                                                                
PythonExtension.cpp::startup()(2): <module>   

To solve it just install the libfontconfig as follow:

apt-get install libfontconfig

After that, the extension will load correctly and the .STEP will appear on File > Import menu

Note: If you have problems with apt-get inside docker, please, check this post: Isaac Sim container 2022.1.0 problem with "urm.nvidia.com" when launching "./run_all_tests.sh" - #2 by Sheikh_Dawood