Unexpected token: react-activity-calendar

[lijimo]

After npm install, npm start, I got the following error message:

./node_modules/react-activity-calendar/build/index.es.js 208:40
Module parse failed: Unexpected token (208:40)
You may need an appropriate loader to handle this file type.
|   const weeks = groupByWeeks(data, weekStart);
|   const totalCount = data.reduce((sum, day) => sum + day.count, 0);
>   const year = getYear(parseISO(data[0]?.date));
|   const theme = getTheme(themeProp, color$1);
|   const labels = Object.assign({}, DEFAULT_LABELS, labelsProp);

To resolve this issue, I have run
npm uninstall react-activity-calendar and afterwards npm audit fix --force.

However, I do not know what impact this can have, but it works for building the website successfully.