So, we’ve just concluded that insync is not showing any notifications under Xubuntu 15.04.
Any way I can configure insync to generate debug information, perhaps setting some environment variable? I could run it that way, and then recreate a scenario where a notification should be shown, so you might have adequate information to debug the issue?
Or perhaps run insync with gdb, as you explained [here] ([Xubuntu] Segmentation fault in spite of little or no syncing activity)?