--- a/toolkit/mozapps/installer/upload-files.mk
+++ b/toolkit/mozapps/installer/upload-files.mk
@@ -7,21 +7,25 @@ ifeq (cocoa,$(MOZ_WIDGET_TOOLKIT))
 MOZ_PKG_FORMAT  = DMG
 else
 ifeq (,$(filter-out WINNT, $(OS_ARCH)))
 MOZ_PKG_FORMAT  = ZIP
 else
 ifeq (,$(filter-out SunOS, $(OS_ARCH)))
    MOZ_PKG_FORMAT  = BZ2
 else
-  ifeq (android,$(MOZ_WIDGET_TOOLKIT))
-    MOZ_PKG_FORMAT = APK
-  else
-    MOZ_PKG_FORMAT = TGZ
-  endif
+   ifeq (,$(filter-out gtk3, $(MOZ_WIDGET_TOOLKIT)))
+      MOZ_PKG_FORMAT  = BZ2
+   else
+      ifeq (android,$(MOZ_WIDGET_TOOLKIT))
+          MOZ_PKG_FORMAT = APK
+      else
+          MOZ_PKG_FORMAT = TGZ
+      endif
+   endif
 endif
 endif
 endif
 endif # MOZ_PKG_FORMAT
 
 ifeq ($(OS_ARCH),WINNT)
 INSTALLER_DIR   = windows
 endif