Files can be sorted in different ways in SOFM. This option is available from the dropdown menu in the top SOFM bar or from the folder view context menu (right-click):
Choose whether to sort by name, date or original file type. Folders and files are sorted separately and the list of folders is placed before the list of files. In sorting by “original type”, the folders are sorted by the complete name but the files - by extension if the file is not encrypted or by the extension used before encryption if the file is encrypted. Dropbox does not support date-sorting for folders and therefore in this case sorting by date affects only the order of files.