I seem to remember automatic updates were available for downloaded versions in 0.16, but I may be mistaken.
Anyway, if you navigate to About > Check Updates, you get a Notice "No new updates available" Confirm popup. As I post this, there have been three updates since. The current version is 0.17.14.
So the popup should be saying there is a new version, right? And should be offering an option to update, right? Or am I out of luck because I downloaded the game from the website instead of using Steam?

When are website downloaded copies of the game going to get auto-updates enabled?