Using Legecy Versions of the Hugo Static Site Generator

While upgrading Hugo (the static site generator I use to make this blog), I noticed a few errors surfacing: WARNING: calling IsSet with unsupported type "invalid" (<nil>) will always return false. After looking around for this I got a hit: Amusingly, a coworker had asked this question a few weeks earlier and discovered the error was related to deprecated functionality in a new version of Hugo that my current theme still relied on.