Reviewed June 3, 2022
When in Edit mode, clicking to open a link in a new browser tab or window loads the new page without the Flex UI header, removeing 'editor.html/' from the page URL in the location bar. Opening in the same tab works normally.
The vendor considers this to be 'normal' functionality.
Workaround: adding 'editor.html/' back into the URL returns the Flex UI header and normal functionality.