Macbook notification banner smudge

whenever the notification banner that appears on the top right of my screen appears, it's covered by a smudge. I can't find any other other answers online that deals with this problem and it's starting to really annoy me.

Solution 1:

Try to completely disable Notification Center, reboot, then reenable.

To do so, (with caution, of course) try the following:

• Launch the Terminal app from /Applications/Utilities, enter the following command, and press Return:

launchctl unload -w /System/Library/LaunchAgents/com.apple.notificationcenterui.plist

• Reboot

• Now re-enable Notification center:

launchctl load -w /System/Library/LaunchAgents/com.apple.notificationcenterui.plist