Block-Quick-Switch: double click on "switch back" -> logout

hi,

if you configured some users for quick-switch block, mascqueraded as one of them via the block link and you want to switch back, you get some problems, if you click too fast twice on switch-back-link.

I see, that after double click I am logged out and masqueraded as anonymous user.

The block content:

"You are masquerading as MyUser.
* Switch back"

...after double click on switch-back-link:

"You are masquerading as Anonymous.
* Switch back"

You only get de-masquerated by a new login to page.