When expanding menu, on certain menu pages, menu items disappear.

[alanjacobmathew]

Versions Tested: 6.5-beta3, 6.4.3.
Browser: Chromium, FF

When accessing the WP dashboard, usually the menu items are always available on the left side of the screen. But on certain pages like(Setting), when trying to expand the menu, the menu items disappear(or the user have to scroll to the top to access it). The left side becomes empty.

How To Reproduce

• Open the WP dashboard and collapse the Menu.
• Click on Settings Menu (wp-admin/options-general.php).
• Scroll to the bottom of the Settings page.
• Expand the menu.

• Again scroll to top or bottom and the menu items appear.

[alanjacobmathew]

Expand Menu bug