In some cases “old flight simmers” are better than paid professional beta testers, customer support (zendesk) or Microsoft MVP
Workaround.
Download and install older graphics card drivers for example Nvidia 466.77
No need
Backup file named ToolBar.css
Official\OneStore\fs-base-ui-pages\html_ui\Pages\ToolBar
After that go to
Official\OneStore\fs-base-ui-pages\html_ui\Pages\ToolBar\
In notepad++ or notepad open file named ToolBar.css
Go to line 46 (opacity)
Change 1 to 0
Before
After
Save changes and run MSFS