`variable??` cannot be resolved or is not a field of `ClassX` Java type.qute(UnknownProperty)

[geertvanleemputten]

Example:
{#formselect value=company.address.country.id?? /}

id?? will get marked in red:
id?? cannot be resolved or is not a field of model.Country Java type.qute(UnknownProperty)

[angelozerr]

Could you share your project please.