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
if (path == null)
					return;
				final File rootDir = new File(path);
				ProgressMonitorDialog pm = new ProgressMonitorDialog(getShell());
				IRunnableWithProgress r = new IRunnableWithProgress() {
					public void run(IProgressMonitor monitor) {
						monitor.beginTask(Messages.searchingTaskName,
								IProgressMonitor.UNKNOWN);
						search(rootDir, existingPaths, foundBrowsers, monitor);
						monitor.done();
					}
				};
				try {
					pm.run(true, true, r);
				} catch (InvocationTargetException ex) {
					Trace.trace(Trace.SEVERE,
							"Invocation Exception occured running monitor: " 
									+ ex);
				} catch (InterruptedException ex) {
					Trace.trace(Trace.SEVERE,
							"Interrupted exception occured running monitor: " 
									+ ex);
					return;
				}
				if (pm.getProgressMonitor().isCanceled())
					return;
				List browsersToCreate = foundBrowsers;
				if (browsersToCreate.isEmpty()) { 
					WebBrowserUtil.openMessage(Messages.searchingNoneFound);
					return;