The ability to toggle gsettings for location-mode from path-bar (those button folder) defaults to filename-entry (the location bar you type in) is what really bothers me. It means I can't paste filepaths into a just opened File dialog (it errors out unless you first type ctrl-l, ., `, or /).

Additionally, the old type-ahead complete was removed from filename-entry. Arch at least has a patch set to put this back, but the location-mode thing is resistant to fixing. I changed the default initialization with a simple patch to gtkfilechooserwidget.c but it only works for the first time I File->Open in a gtk3 application. The second reverts back to pathbar.