The word list in the desktop app is embedded in the Electron bundle app.asar. We can see from the comment that the origin of the embedded list of the Electronic Frontier Foundation.
To support multiple lists the development team might need to extract the list from the app bundle to a dedicated .txt file in the app path. That would make the list extensible because it’d simply be a reference to a file path.
// CONCATENATED MODULE: ./jslib/src/misc/wordlist.ts
// EFF's Long Wordlist from https://www.eff.org/dice
const EEFLongWordList = [
'abacus',
....
];