fix: keep scrolling disabled while there is a visible InternalOverlay.

[yvmunayev]

• [x] I have searched the issues of this repository and believe that this is not a duplicate.

Describe the bug

When there are several visible InternalOverlay and one is hidden, the scroll is enabled.

To Reproduce 🕹

Steps to reproduce the behavior:

1. Go to HelpText
2. Click on HelpText info button
3. Hover HelpText error button
4. MouseLeave HelpText error button
5. See error

Expected Behavior 🤔

As long as there is a visible Internal Overlay, the scroll must be disabled.