(Required) (String) Which file to register or return
If $file is ‘css’ or ‘js’, it will be registered in WordPress.
If $file is ‘reboot’, the ‘reboot.css’ filepath will be returned.
If $file is empty, the Bootstrap version number is returned as a string of either ‘v3’, ‘v4a5’, or ‘latest’.
This checks the Bootstrap Version set in Nebula Options.
No HooksThis function does not have any filters or actions available. Request one?
This function can not be short-circuited with an override filter. Request one?