For code blocks inside a custom tag, an extra indent is added to the final output.

[Norlandz]

For code blocks inside a custom tag, an extra indent is added to the final output.

eg:

html = `
<ms-code-block><pre>      <code><span class="hljs-comment"># Our data from the previous step</span>
target_token_id = <span class="hljs-number">12</span>
y[target_token_id] = <span class="hljs-number">1</span>
</code></pre>
</ms-code-block>
`;

Expect:

```
foo = bar
```

Actual:

    ```
foo = bar
```

This leads to an invalid code block in markdown.

• Note:
  I tried to tweak the replacement function, but a lot of times it doesnt produce the output strictly.
  It seems its later reformatted again.
  The later reformat is somehow dependent on having leading space or not.
  eg:

  replacement: function (content, node, options) {
    // adding NN or not here changes the later reformat ...
    return 'NN\n\n' + fence + language + '\n' + code.replace(/\n$/, '') + '\n' + fence + '\n\n';
  },
  

• Note:
  This is also related to the space gap I mention in
  Fail to detect coding block when there is a space gap between <pre> <code>. #498

[Norlandz]

for reproducing this bug, the rule is:

if 
&& the pre is inside a custom tag 
&& so you create a `turndownService.addRule('preCodeBlock', {` which is near the same as the source code.
&& there is no non-space text before the pre
&& there is a any leading space like: `<pre><code>      ` & `<pre>      <code>`