Window horizontal scrollbar will change upon hovering the mouse over "flat" Navigation Menu items

• Type: Regression Bug
• Status: Closed
• Resolution: Fixed
• Affects Version/s: 7.1.X, 7.2.10 DXP FP1, 7.2.X, Master
• Fix Version/s: 7.2.10 DXP FP3, 7.2.X, 7.2.1 CE GA2, Master
• Component/s: Frontend Infrastructure
• Labels:
  • ee-ts
  • liferay-fixpack-dxp-3-7210
• Branch Version/s:
  7.2.x
• Backported to Branch:
  Committed
• Fix Priority: 4
• Git Pull Request: https://github.com/brianchandotcom/liferay-portal/pull/79617/

Reproduction steps:
1) Get vanilla 7.2 and patch it with dxp-1-7210, start the server, login as admin
2) On the Welcome page, hover the mouse on the Navigation Menu widget and click on the "+" button
3) Add as many (top-level) pages as needed to make the Navigation Menu expand at 100% of the page width
4) Hover the mouse on the pages in the Navigation Menu widget from left to right and, at the same time, observe the very bottom horizontal scrollbar of the browser's window
(on Mac, you should use the right arrow key after the 4th? menu item to move the horizontal scrollbar, while hovering)

Expected behavior: No horizontal scrollbar to appear
Actual behavior: As we hover on pages from left to right, the horizontal bar will appear, using right arrow key, will move the site out of the screen.

This is a regression caused by LPS-85974