Settings -> Preferences -> Backup/Auto-Completion
Enable auto-completion on each input.
- Function completion
- Word completion
(I have a few plugins installed but I'm pretty sure this is a setting in the vanilla install of NP++)
Personally I just changed from NP++ to
Atom.io (just a week or so ago) because the amount of files open where really hard to jump between in NP++, using the smaller and smaller tabs just became a guessing game, so I needed something with a File tree on the left to navigate in.