In the section of the account, you will be able to select the format in which you want new documents to be created.
Do the following:
1.Click the user mini-avatar in the lower left corner of the Navigation bar.
2.Click > .
3.Select the desired option in the field.
The document icons displayed in the application selection menu and add file menu depend on the selected file format.
: Microsoft Office files
: MyOffice Documents
: OpenDocument files