After numerous unsuccessful attempts using ⌘F (Finder) and Spotlight, I switched to Find Any File and searched for content containing DuckDuckGo (my chosen search engine) and a file name ending in .plist which turned up several files. I then opened the suspects in Xcode to confirm it was the file I was looking for.

That technique should work in almost any version of MacOS. If Xcode isn't available to verify it is the correct file TextEdit should work.



"All you've got to do is own up to your ignorance
honestly, and you'll find people who are eager to
fill your head with information"
--Walt Disney