src/vs/workbench/contrib/notebook/browser/notebookEditorDecorations.ts/NotebookDecorationCSSRules/_getCSSTextForModelDecorationContentClassName
class NotebookDecorationCSSRules:	private _getCSSTextForModelDecorationContentClassName(opts: IContentDecorationRenderOptions | undefined): string {
		if (!opts) {
			return '';
		}
		const cssTextArr: string[] = [];

		if (typeof opts !== 'undefined') {
			this._collectBorderSettingsCSSText(opts, cssTextArr);
			if (typeof opts.contentIconPath !== 'undefined') {
				cssTextArr.push(strings.format(_CSS_MAP.contentIconPath, DOM.asCSSUrl(URI.revive(opts.contentIconPath))));
			}
			if (typeof opts.contentText === 'string') {
				const truncated = opts.contentText.match(/^.*$/m)![0]; // only take first line
				const escaped = truncated.replace(/['\\]/g, '\\$&');

				cssTextArr.push(strings.format(_CSS_MAP.contentText, escaped));
			}
			this._collectCSSText(opts, ['fontStyle', 'fontWeight', 'textDecoration', 'color', 'opacity', 'backgroundColor', 'margin'], cssTextArr);
			if (this._collectCSSText(opts, ['width', 'height'], cssTextArr)) {
				cssTextArr.push('display:inline-block;');
			}
		}

		return cssTextArr.join('');
	}