Ok, this is related to the post from July (Error while setting up the stand-alone FreeSewing development environment) It’s not just Sabrina that is causing the error, though - Devon, Jett, Sarah and Sunny are also included. With Devon getting an additional error on the webpage as well.
There is also, apparently, a problem with webpack - @tailwindcss/node/dist/index.mjs for build dependencies failed at ‘import(e)’. and @tailwindcss/node/node_modules/jiti/lib/jiti.mjs for build dependencies failed at ‘import(id)’. Obviously, webpack would just need to be solved by a different version, as it’s not freesewing maintained.
Following the information at Codeberg issue 499 and adding Devon, Jett, Sabrina, Sarah, and Sunny, plus the plugin path package mentioned, then running npm install did solve the non-webpack errors.