This make_neunique function template is being rendered with an invalid parameter pack in the generated docs.
Source:
template<class T, class... Args>
typename std::enable_if<
!std::is_array<T>::value,
neunique_ptr<T>>::type
make_neunique(Args&&... args);
Rendered output:
template<
class T,
class... Args>
neunique_ptr<T>
make_neunique(Args...&&... args)
requires !std::is_array<T>::value;
The ... appears twice around Args, which is not valid C++.