If you expand the personal tools dropdown menu without retracting it, and then you roll back to the top, the dropdown menu DOM is still clickable.

Steps to replicate the issue:

• Log in.
• Visit a page with vector-2022 skin. (e.g. https://en.wikipedia.org/wiki/Lorem_ipsum?useskin=vector-2022 )
• Roll down until you see the stiky header. Click the personal tools dropdown menu on the top-right.
• Roll back up to the top without clicking anything.
• Open the Developer Tools and choose the Inspect Element Mode. You will see that on the top-right of the page, some invisible buttons are floating in thin air.

Note: .uls-dialog-sticky-hide #vector-sticky-header { display: none; }should solve the problem.