so change it to notebookbar
should take effect:
<user_interface>
<mode type="string" desc="Controls the user interface style. The 'default' means: Take the value from ui_defaults, or decide for one of classic or notebookbar (default|classic|notebookbar)" default="default">notebookbar</mode>
<use_integration_theme desc="Use theme from the integrator" type="bool" default="true">true</use_integration_theme>
</user_interface>
if not… then that is indeed strange. But it’s also worth mentioning that as for that version NC Notebookbar mode is still not ready (it will be very soon ) but meanwhile you can switch off use_integration_theme
by setting it to false