A common request from users of Panic Button is to be able to minimize all Firefox browser windows to the system tray when clicking the Panic Button or pressing the F9 key, to make web browsing less conspicuous. Well, there is a way to do that.
Download and install MinimizeToTray Revived, a Firefox extension. After installation, go to Tools → Add-ons, locate the entry for Panic Button in the list of installed extensions, then click Options. Select the Panic Button action to "Minimize all windows." Then every time the Panic Button action is invoked, all open Firefox windows will be minimized to the system tray, instead of to the Taskbar.
MinimizeToTray Revived is not developed by AE Creations, so any questions and comments about it should be directed to its developer.