I’m using Arch and recently updated to GNOME 3.12 and immediately noticed an annoying visual issue whereby the GNOME Files application (aka Nautilus) would display files interwoven with folders whereas I strongly prefer showing folders first then files. The Files app does have a preference called “Sort Folders before Files” available but it doesn’t work, enabling it doesn’t do anything and checking the preference dialog a second time shows it back to being unchecked.
To work around the issue, I ended up using the dconf-editor application to change it manually. Navigate to the org.gnome.nautilus.preferences key and set the option sort-directories-first to true.
To achieve the same effect for the Open and Save file dialogs, navigate to the key org.gtk.Settings.FileChooser and set the option sort-directories-first to true.