Reopen a closed GUI of a running program

Question

When I use Truecrypt or Skype GUI and then (by mistake) push the X button to close it I can still see they are running (using ps-e).

In the case with Skype I can even see I am logged in. If I try to reopen it I will get a new instance. In the case with Truecrypt I can't even reopen the GUI since it says "Truecrypt is already running" (not literally).

In these cases, is there a way to bring up the GUI of a program that is already running, using Unity or command-line? Right now I simply kill the process and restart it.

Answer 1

This is a result of Canonical's policy not allowing traditional system tray icons anymore, let alone a few exceptions.

Truecrypt and some versions of Skype still use the old-fashioned way of advertising their presence in the background, and to allow such system tray icons to be seen, you can run the following command:

gsettings set com.canonical.Unity.Panel systray-whitelist "['all']"

You may need to log out and in again.

To revert this change:

gsettings set com.canonical.Unity.Panel systray-whitelist "['JavaEmbeddedFrame', 'Mumble', 'Wine', 'Skype', 'hp-systray']"