extensions/markdown-language-features/src/preview/documentRenderer.ts/MdDocumentRenderer/_getScripts
class MdDocumentRenderer:	private _getScripts(resourceProvider: WebviewResourceProvider, nonce: string): string {
		const out: string[] = [];
		for (const resource of this._contributionProvider.contributions.previewScripts) {
			out.push(`<script async
				src="${escapeAttribute(resourceProvider.asWebviewUri(resource))}"
				nonce="${nonce}"
				charset="UTF-8"></script>`);
		}
		return out.join('\n');
	}