The Smart menu option doesn’t persist in the new Header builder (this option is deprecated, doesn’t work, removed).
You can submit a request for adding a similar option for the Header builder here – https://www.8theme.com/taskboard/ , there is no ready solution.
You can enable header full width for the Bottom header area via Theme Options > Header builder or try to change the menu and header like this – https://xstore.8theme.com/https://prnt.sc/vih4us
