When activating Zend mode, there's a message displayed for the user to alert about this and the user can close that message clicking on the red cross.
One issue is that if the user do not close that message, when he closes Zend mode (by clicking the arrow on the top right) and clicking it again, the message is duplicated. Everytime the user activates Zend mode, the info message is duplicated The other issue is that when the message is not closed and Zend mode is deactivated, the message remains displayed.
STEPS - Open Piwik installation - Click on the arrow in top right - A message about Zend mode activated should be displayed - Without closing this message, click on the arrow in the top right (issue number 2, message should disappear) - Click again on that arrow (issue number 1, message is duplicated)
I think this is a regression from creating an angular directive for notifications. Should be fixed now.
When closing Zen mode a not previously closed message will still stay. This was never implemented but could be done. So will leave the ticket open
Fixed in master, forgot to close.