It works with me but with a little trick.

Never use a backup activity as your current activity.

For instance if my current activity is bkup1 and i want to backup my current desktops i must create a new activity and save it as bkup2.
After this the current activity will be bkup2 and bkup1 the backup activity.

If for any reason the desktop crash and i want to recover it then i just need to switch to activity bkup1 as the bkup2 (current activity) will be messed up with the crash.
To keep the bkup1 safe it will be necessary to delete the messed bkup2 and create it again.