Issue 1:
Feature request

What is the expected behavior?

Build simple bundle without any runtime chunk code overhead.

Stackoverflow question: https://stackoverflow.com/questions/68369841/webpack-simple-bundle-no-runtime-chunk

What is motivation or use case for adding/changing the behavior?

Building simple, independent bundles. No need for additional runtime code (useless overhead).

How should this be implemented in your opinion?

Add either:

target: 'bundle'

optimization.runtimeChunk: 'disabled'

Are you willing to work on this yourself?

no

Issue 2:
Code in question:

import cls from 'classnames';

// ...
const dropdownClassName = cls({
[baseClassName]: true,
[`${baseClassName}_is-open`]: uiState.isOpen,
[`${baseClassName}_is-selected`]: isSelected,
[`${baseClassName}_is-invalid`]: canShowErrors && !isValid,
[`${baseClassName}_is-valid`]: canShowValid && isValid,
[`${baseClassName}_is-filled`]: Boolean(this.getValue()),
});

After beta.8 there is SyntaxError: Unexpected ) (note 1 opening paren and 2 closing ones):

var dropdownClassName = /* harmony import */ __WEBPACK_IMPORTED_MODULE_2_classnames___default.a.call(
undefined,
_cls = {},
_cls[baseClassName] = true,
_cls[baseClassName + '_is-open'] = uiState.isOpen,
_cls[baseClassName + '_is-selected'] = isSelected,
_cls[baseClassName + '_is-invalid'] = canShowErrors && !isValid,
_cls[baseClassName + '_is-valid'] = canShowValid && isValid,
_cls[baseClassName + '_is-filled'] = Boolean(this.getValue()),
_cls
));

After beta.7 everything is fine (2 opening and 2 closing parens):

var dropdownClassName = /* harmony import */ __WEBPACK_IMPORTED_MODULE_2_classnames___default.a.bind()((
_cls = {},
_cls[baseClassName] = true,
_cls[baseClassName + '_is-open'] = uiState.isOpen,
_cls[baseClassName + '_is-selected'] = isSelected,
_cls[baseClassName + '_is-invalid'] = canShowErrors && !isValid,
_cls[baseClassName + '_is-valid'] = canShowValid && isValid,
_cls[baseClassName + '_is-filled'] = Boolean(this.getValue()),
_cls
));

Code was run through babel with this .babelrc

{
"plugins": [
"transform-decorators-legacy",
"transform-class-properties",
"transform-proto-to-assign",
"transform-object-set-prototype-of-to-assign",
["transform-builtin-extend", {
"globals": ["Error"],
"approximate": true
}],
"transform-object-rest-spread",
["transform-es2015-template-literals", { "loose": true }],
"transform-es2015-literals",
"transform-es2015-function-name",
"transform-es2015-arrow-functions",
"transform-es2015-block-scoped-functions",
["transform-es2015-classes", { "loose": true }],
"transform-es2015-object-super",
"transform-es2015-shorthand-properties",
"transform-es2015-duplicate-keys",
["transform-es2015-computed-properties", { "loose": true }],
["transform-es2015-for-of", { "loose" : true}],
"transform-es2015-sticky-regex",
"transform-es2015-unicode-regex",
"check-es2015-constants",
["transform-es2015-spread", { "loose": true }],
"transform-es2015-parameters",
["transform-es2015-destructuring", { "loose": true }],
"transform-es2015-block-scoping",
"transform-es2015-typeof-symbol",
"transform-react-jsx",
"transform-react-display-name"
]
}

Versions of babel packages:

{
"babel-cli": "6.9.0",
"babel-loader": "6.2.4",
"babel-plugin-check-es2015-constants": "6.8.0",
"babel-plugin-transform-async-functions": "6.8.0",
"babel-plugin-transform-builtin-extend": "1.1.0",
"babel-plugin-transform-class-properties": "6.9.1",
"babel-plugin-transform-decorators-legacy": "1.3.4",
"babel-plugin-transform-es2015-arrow-functions": "6.8.0",
"babel-plugin-transform-es2015-block-scoped-functions": "6.8.0",
"babel-plugin-transform-es2015-block-scoping": "6.9.0",
"babel-plugin-transform-es2015-classes": "6.9.0",
"babel-plugin-transform-es2015-computed-properties": "6.8.0",
"babel-plugin-transform-es2015-destructuring": "6.9.0",
"babel-plugin-transform-es2015-duplicate-keys": "6.8.0",
"babel-plugin-transform-es2015-for-of": "6.8.0",
"babel-plugin-transform-es2015-function-name": "6.9.0",
"babel-plugin-transform-es2015-literals": "6.8.0",
"babel-plugin-transform-es2015-object-super": "6.8.0",
"babel-plugin-transform-es2015-parameters": "6.9.0",
"babel-plugin-transform-es2015-shorthand-properties": "6.8.0",
"babel-plugin-transform-es2015-spread": "6.8.0",
"babel-plugin-transform-es2015-sticky-regex": "6.8.0",
"babel-plugin-transform-es2015-template-literals": "6.8.0",
"babel-plugin-transform-es2015-typeof-symbol": "6.8.0",
"babel-plugin-transform-es2015-unicode-regex": "6.8.0",
"babel-plugin-transform-object-rest-spread": "6.8.0",
"babel-plugin-transform-object-set-prototype-of-to-assign": "6.8.0",
"babel-plugin-transform-proto-to-assign": "6.9.0",
"babel-plugin-transform-react-display-name": "6.8.0",
"babel-plugin-transform-react-jsx": "6.8.0",
}