The M4d release added term autocompletion to the Unison Language Server. This means that if you have the Unison LSP installed, you'll get suggestions for possible Unison terms based on the prefix of the term that you've started.
Check it out:
Unison teammate Chris Penner has been hard at work adding LSP tooling improvements. This feature is the latest addition to others like viewing the type of a term on hovering, and in-editor error rendering. Thank you, Chris, for making our developer experience more complete! 💐