To save repetition I refer you to the same issue on the filechooser. It has now been adopted in gtk+ , I think it would help Thunar. http://bugzilla.gnome.org/show_bug.cgi?id=327733
*** Bug 2061 has been marked as a duplicate of this bug. ***
Fixed with revision 22920. 2006-08-28 Benedikt Meurer <benny@xfce.org> * thunar/thunar-navigation-bar.{c,h}, thunar/thunar-path-button.{c,h}, thunar/thunar-navigation-bar-ui.xml, thunar/thunar-path-bar.{c,h}, thunar/thunar-location-button.{c,h}, thunar/thunar-location-bar.{c,h}, thunar/thunar-location-buttons-ui.xml, docs/README.gtkrc, thunar/thunar-location-buttons.{c,h}, thunar/Makefile.am, thunar/thunar-location-entry.{c,h}, thunar/thunar-marshal.list, thunar/thunar-shortcuts-pane.c, thunar/thunar-shortcuts-view.c, thunar/thunar-tree-pane.c, thunar/thunar-tree-view.c, thunar/thunar-window-ui.xml, thunar/thunar-window.c: Synchronize the latest user interface changes in GtkFileChooser. This way the location bar will be used for both the path bar and the path entry widgets, and a simple toggle button controls whether the path entry is visible. This way (nearly) the full width of the window is avail- able for the path bar. Bug #2060.
It messes up the UI of the file manager, and as such will be reverted. The previous behaviour was way better, no matter if it matches the GtkFileChooser or not (I doubt that the recent decisions on GtkFileChooser's UI were well thought anyway, looks more like a quick&dirty hack to make certain people stop screaming).
Full width path bar makes the interface look too busy and wastes too much space. Better keep the user interface clean. Maybe someone will come up with a good solution later.