Bug 293159 [Browser] Search for external browser in Preferences finds > 40 instances of firefox on Ubuntu 64bit, if started in /usr/bin
bundles/org.eclipse.ui.browser/src/org/eclipse/ui/internal/browser/WebBrowserPreferencePage.java
checkedBrowser = BrowserManager.getInstance().getCurrentWebBrowser();
		if (checkedBrowser != null)
			tableViewer.setChecked(checkedBrowser, true);
		
		super.performDefaults();
	}
	/**
	 * Method declared on IPreferencePage. Subclasses should override
	 */
	public boolean performOk() {
		int choice;
		if (internal.getSelection())
			choice = WebBrowserPreference.INTERNAL;
		else
			choice = WebBrowserPreference.EXTERNAL;
		WebBrowserPreference.setBrowserChoice(choice);
		if (checkedBrowser != null) {
			BrowserManager.getInstance().setCurrentWebBrowser(checkedBrowser);
		} else {
			BrowserManager.getInstance().saveBrowsers();
		}
		return true;
	}
	
	public boolean performCancel() {
		BrowserManager.getInstance().loadBrowsers();
		return super.performCancel();
	}
}