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
edit = SWTUtil.createButton(buttonComp, Messages.edit);
		edit.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(SelectionEvent e) {
				IStructuredSelection sel = ((IStructuredSelection) tableViewer
						.getSelection());
				IBrowserDescriptor browser2 = (IBrowserDescriptor) sel
						.getFirstElement();
				IBrowserDescriptorWorkingCopy wc = browser2.getWorkingCopy();
				BrowserDescriptorDialog dialog = new BrowserDescriptorDialog(
						getShell(), wc);
				if (dialog.open() != Window.CANCEL) {
					try {
						tableViewer.refresh(wc.save());
					} catch (Exception ex) {
						
					}
				}
			}
		});
		remove = SWTUtil.createButton(buttonComp, Messages.remove);
		remove.addSelectionListener(new SelectionAdapter() {
			public void widgetSelected(SelectionEvent e) {
				IStructuredSelection sel = ((IStructuredSelection) tableViewer
						.getSelection());
				IBrowserDescriptor browser2 = (IBrowserDescriptor) sel
						.getFirstElement();
				try {
					browser2.delete();
					tableViewer.remove(browser2);