Why LibreOffice?

LibreOffice fully supports Microsoft's newest file formats used for Excel, Word, and PowerPoint. This is the main reason for choosing LibreOffice over OpenOffice.

OpenOffice Writer, while able to open DOCX files just fine, cannot save back to that same format. Since it doesn't support making DOCX files, you have to save the newest MS Word format to something else like DOC, ODT, or RTF.

OpenOffice Calc has the same limitation when it comes to XLSX files; it can open them but cannot save back to that same format. The same is true for Impress and PPTX files, and Base and ACCDB files.

ref: www.lifewire.com/libreoffice-vs-openoffice-who-wins-2512178