Pop-up alerts/messages/notifications cover parts of the Artemis UI until dismissed

[just-max]

Describe the bug

This is about the pop-up notifications (see screenshot). Artemis used to show them in a separate container at the top of the page (which had the minor problem of pushing down the rest of the page). Now Artemis shows them desktop-notification-style in the top-right corner of the screen, which means anything behind the pop-up is inaccessible until it times out or is clicked away. This is really just a minor inconvenience, but when trying to get through some repetitive task (e.g. marking) it really gets annoying.

To Reproduce

• Go to some page that shows pop-up notifications
• Get a pop-up notification
• Try to click on something behind the notification
  • wait until the notification goes away
  • move the mouse to the :heavy_multiplication_x: to close the notification

Expected behavior

Since the notifications can't be interacted with as far as I can tell, they could be translucent and not prevent clicking behind them. Or they could be at the bottom of the screen so that anything they obscure could just be scrolled into view.

Screenshots

(have to wait for the notifications to go away, or close each one)