Comment 126 for bug 1170647

While I'm far from being an expert in the Unity source code, taking a look at it (more precisely, file launcher/ApplicationLauncherIcon.cpp, function ApplicationLauncherIcon::ActivateLauncherIcon in Vivid) it seems this behaviour comes from a patch made to fix the bug #753938 "Launcher - Open Trash window prevents Nautilus being launched when a user clicks on the Nautilus Launcher icon"[1]. That fix launches a new Nautilus window if the currently opened Nautilus windows are the trash or devices mounted in /media/<username>/.

But I think the previous behaviour is correct, i.e. the trash and devices launcher icons should be thought as just shortcuts to the Files/Nautilus application, not as separate applications; clicking on the Trash icon opens a trash window *in Nautilus*, so when you click on the normal Nautilus launcher icon it should bring that Trash window back, not open a separate window with the Home folder. This is way is done for example in Mac OS X, where clicking on the Trash icon on the dock brings a Finder window, and if you click the Finder icon afterwards it brings back the Trash window, not a new window.

This way may be annoying for some users that think of the Trash/Devices icons as separate applications, but I think it's more consistent and less workflow-disruptive when you are working with devices/trash windows.

[1]: https://bugs.launchpad.net/ubuntu/+source/unity/+bug/753938