This bug has been reported since 2009 and was marked resolve in version 2.5, however it has never worked for me. The editor no longer shows it as an error - ie. underlined even though it compiles fine - so that is great! However, the autocomplete functionality does not work.

Case:
Upon setting an alias for a namespace:

namespace pang = pangolin;

The IDE is not able to autocomplete via 'pang::'.