When exporting a Draw in LibreOffice Draw, the “Save Dialog” box does not show the options “Save as type” and the “Automatic file name extension” and “Selection” checkbox.
http://www.paulchung.org/uploads/5/2/8/6/52862069/2914344_orig.png
Please try if it helps: menu "Tools : Options : LibreOffice : General : Open/Save Dialogs : Use LibreOffice dialogs".
That made the trick! Thanks! For developers, I forgot to say that I’m using Deepin File Manager (dde-file-manager) on Deepin 15.4 (if this information helps). I already open an issue on dde-file-manager git (Crashes when there are too many files · Issue #51 · linuxdeepin/dde-file-manager · GitHub) and here in hope that this issue could become public (but I didn’t know exactly if it is an LibreOffice or Deepin issue).
Same problem in Impress, and changing the open/save dialogs does not bring up the ‘selection’ option.