Commented out code refers to an issue that has been resolved for some time.

[GuySartorelli]

There is some commented out code that refers to an issue that has been resolved for some time.

silverstripe-admin/client/src/legacy/ToggleCompositeField.js

Lines 6 to 7 in d3fc48c

	// TODO Enable once https://github.com/webpack/extract-text-webpack-plugin/issues/179 is resolved. Included in bundle.scss for now.
	// require('../../../thirdparty/jquery-ui-themes/smoothness/jquery-ui.css');

The referenced issue was resolved in February 2018.
This comment should be removed.
The commented out code should either be removed outright, or be uncommented and the relevant parts removed from bundle.scss.