Permalinks missing?

[Anton Averin]

Even though it's possible to request tableOfContent in allMdx and it's properly generated, permalinks seem to be missing on all headline elements.

This could be related to my custom MDXProvider with custom components. Anything special I need to write there? Here is my current state

import { MDXProvider } from '@mdx-js/react'
import React from 'react'
import { H1, H2, H3, PM} from '@src/style/mdxStyle'
import styled, { css } from 'styled-components'

export default ({ children }) => (
  <MDXProvider
    components={{
      // Map HTML element tag to React component
      h1: H1,
      h2: H2,
      h3: H3,
      p: PM,
      li: styled.li`
        ${props => props.theme.typography.paragraph.M}
      `
    }}
  >
    {children}
  </MDXProvider>
)

[Anton Averin]

I check props for the component and there are only children

FYI, for regular .md in Gatsby, every headline also generates a small anchor inside with the '#link' for permalink support and those links are then later used in table of contents

[Anton Averin]

It's the same problem in kitchen-sink example
https://gatsby-mdx-kitchen-sink.netlify.com/posts/non-page-basic-toc#something-iffi

Links are there in the table of contents but there are not present on the headlines in the generated text

[Anton Averin]

Is this PR the solution?
#389

[Anton Averin]

Also #396

[Anton Averin]

Closing as a duplicate, let's follow #396 instead