How to remove a section from the table of contents?

问题

Or in other words: is there something like \tocless for Rmd's? I found something for Latex here, but could not find anything for an Rmd.

Changing toc-depth is not an option:

output:
  html_document:
    toc: true
    toc_float:
      collapsed: false
    toc_depth: 2

Reproducible example:

---
title: "Untitled"
author: "SQC"
date: "7 Juni 2018"
output:
  html_document:
    toc: true
    toc_float:
      collapsed: false
    toc_depth: 2
    theme: yeti
---

## Sec. 1

bla

## Sec. 2 - not part of content

bla

来源：https://stackoverflow.com/questions/50740687/how-to-remove-a-section-from-the-table-of-contents