diff --git a/src/Makefile.am b/src/Makefile.am
index 7b457ce..c43e390 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -20,7 +20,7 @@ xfce4_taskmanager_LDADD = 						\
 
 xfce4_taskmanager_SOURCES =						\
 	main.c								\
-	process-window_ui.h						\
+	process-window_ui.h		process-window-gtk3_ui.h	\
 	process-window.c		process-window.h		\
 	process-monitor.c		process-monitor.h		\
 	process-tree-model.c		process-tree-model.h		\
@@ -28,7 +28,7 @@ xfce4_taskmanager_SOURCES =						\
 	process-statusbar.c		process-statusbar.h		\
 	exec-tool-button.c		exec-tool-button.h		\
 	settings-tool-button.c		settings-tool-button.h		\
-	settings-dialog_ui.h						\
+	settings-dialog_ui.h		settings-dialog-gtk3_ui.h	\
 	settings-dialog.c		settings-dialog.h		\
 	settings.c			settings.h			\
 	task-manager.c			task-manager.h			\
@@ -63,12 +63,16 @@ xfce4_taskmanager_SOURCES += task-manager-skel.c
 endif
 
 if MAINTAINER_MODE
-BUILT_SOURCES = process-window_ui.h settings-dialog_ui.h
+BUILT_SOURCES = process-window_ui.h settings-dialog_ui.h process-window-gtk3_ui.h settings-dialog-gtk3_ui.h
 process-window_ui.h: process-window.ui
 	$(AM_V_GEN) exo-csource --static --strip-comments --strip-content --name=process_window_ui $< >$@
 settings-dialog_ui.h: settings-dialog.ui
 	$(AM_V_GEN) exo-csource --static --strip-comments --strip-content --name=settings_dialog_ui $< >$@
+process-window-gtk3_ui.h: process-window-gtk3.ui
+	$(AM_V_GEN) exo-csource --static --strip-comments --strip-content --name=process_window_ui $< >$@
+settings-dialog-gtk3_ui.h: settings-dialog-gtk3.ui
+	$(AM_V_GEN) exo-csource --static --strip-comments --strip-content --name=settings_dialog_ui $< >$@
 endif
 
-EXTRA_DIST = process-window.ui settings-dialog.ui
+EXTRA_DIST = process-window.ui settings-dialog.ui process-window-gtk3.ui settings-dialog-gtk3.ui