src/vs/editor/standalone/browser/standaloneThemeService.ts/StandaloneThemeService/registerEditorContainer
class StandaloneThemeService:	public registerEditorContainer(domNode: HTMLElement): IDisposable {
		if (dom.isInShadowDOM(domNode)) {
			return this._registerShadowDomContainer(domNode);
		}
		return this._registerRegularEditorContainer();
	}