Error after npm update

After installing, I run `npm start` and am prompted to run `npm update`. I do that, and then `npm start` again. This error is generated:
```
$ npm start
(node:28902) ExperimentalWarning: The fs.promises API is experimental

> extend-block-example@1.0.0 start
> parcel watch --no-hmr assets/js/extend-block-example.js -d dist

🚨 Git/extend-block-example-wp-plugin/assets/js/spacing-control.js: function __clone() {
var node2 = new Node();
for (var key in this) {
// Do not clone comments tha...... } could not be cloned.
var node2 = new Node();
for (var key in this) {
// Do not clone comments tha...... } could not be cloned.
at Object.serialize (v8.js:202:7)
at _default (Git/extend-block-example-wp-plugin/node_modules/@babel/core/lib/transformation/util/clone-deep.js:22:34)
at normalizeFile (Git/extend-block-example-wp-plugin/node_modules/@babel/core/lib/transformation/normalize-file.js:84:36)
at normalizeFile.next ()
at run (Git/extend-block-example-wp-plugin/node_modules/@babel/core/lib/transformation/index.js:29:50)
at run.next ()
at Function. (Git/extend-block-example-wp-plugin/node_modules/@babel/core/lib/transform-ast.js:26:41)
at Generator.next ()
at evaluateSync (Git/extend-block-example-wp-plugin/node_modules/gensync/index.js:251:28)
at Function.sync (Git/extend-block-example-wp-plugin/node_modules/gensync/index.js:89:14)
```

Reproduce the failure by running npm update followed by npm start, then inspect assets/js/spacing-control.js alongside the Babel clone-deep stack trace. Determine what dependency state allows npm start to complete successfully; done means the Parcel watch command runs without this cloning error.

Written by the indexing model from the issue text.