Here, let me demo it via a short video: Malwaretips app _Chrome 05-01-2017.mp4I cannot replicate the glitch you are talking about.
If you hover over the alert icon and move your cursor to the left a bit then yes the message drop down appears.
But to expand these you need to click "Show all" in the bottom left corner of the dropdown.
It looks perfectly normal to me but maybe @Jack can have a look.Here, let me demo it via a short video: Malwaretips app _Chrome 05-01-2017.mp4
I stop my cursor on the 'Alert' icon that has a red unread indicator. Then, I donot move the cursor, but the red indicator goes off (when the alerts are displayed) and the width of the 'Alert' icon decreases, the 'Alert' icon and the 'Messages' icon shift a bit to the right.
So, now, the cursor being stable where it was, the 'Messages' icon comes beneath the cursor. Hence the messages panel opens up as shown in the video.
Didn't you notice the slight shifting of the two icons. The 'Alert' icon is below the cursor and suddenly after the shift, the 'Messages' icon comes under it, the cursor being stagnant.