easy bug. but very unintuitive. the application should be always aware which extension to take depending on the DataNode type and not on its name.
steps to reproduce:
- start current extapp (commit: a75c8c4c60297849c0a17ce47099ee37761a6862)
- load Pic3D
- rename Pic3D in the DataManager to Pic.3D
- try to save it in some dir
- the application will show an error "no suitable file format found"