message: Allow one level of {...} inside caption
  This closes
diff: @@ -242,7 +242,7 @@ export class SectionNodeProvider implements vscode.TreeDataProvider<Section> {
  getCaption(lines: string[], env: {name: string, start: number, end: number}) {
  const content = lines.slice(env.start, env.end).join('\n')
  - const result = /(?:\\caption(?:\[[^\[\]]*\])?){(.*?)}/gsm.exec(content)
  + const result = /(?:\\caption(?:\[[^\[\]]*\])?){((?:[^\{\}]*(?:\{.*?\})*[^\{\}]*)*?)}/gsm.exec(content)
  if (result) {
  // Remove indentation, newlines and the final '.'
  return result[1].replace(/^ */gm, ' ').replace(/\r|\n/g, '').replace(/\.$/, '')
  