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I installed i3 desktop environment and then removed it via software manager since I didn't like it very much.
Now I started to use unity (default) back again. However, now I have a white over blue notifications on the upper left of my screen. I usually see them when wifi is connected or I received an email.
This notification also appears on the login screen and does not let me to write my password during the check of preferred wirelesses.
I need to remove this notification thing.