### Bug description

Write a very long line of text for a code block in a list using indentation or with backtick fences but without a language tag.

The grey background does not span the whole text; it is only present for the initially visible section.

Here is the rendering of the example document with each code block scrolled a bit.

<img width="1043" alt="image" src="https://github.com/quarto-dev/quarto-cli/assets/362187/3c469585-3b1b-431e-850a-0e20d8e40768">

Code blocks introduced with backtick fences and language tags do not have this problem. Code blocks outside lists do not have this problem.


### Steps to reproduce

The `_quarto.yml`:

```yaml
project:
  type: website

format:
  html:
    toc: true
    theme: cosmos
```

The `index.qmd`:

````markdown
---
title: home
---

## Code blocks via indentation

We like code.

This code block has no language tag, so it is left with a white background.

    some code blocks are really long and do not know when to quit because they are presenting some information that was produced by some external tool and wrapping that text might change how it is interpreted by the reader.

## Listed code blocks via indentation

*   *This is also important*

    This code block is introduced with indentation. It has no language tag,
    but it is presented with a grey background. That background only spans the
    initially visible text and is not present when scrolling.

        some code blocks are really long and do not know when to quit because they are presenting some information that was produced by some external tool and wrapping that text might change how it is interpreted by the reader.

## Listed code blocks via fencing; no language

*   *This is important*

    This code block is introduced with backtick fences. It has no language
    tag, but it is presented with a grey background. That background only
    spans the initially visible text and is not present when scrolling.

    ```
    some code blocks are really long and do not know when to quit because they are presenting some information that was produced by some external tool and wrapping that text might change how it is interpreted by the reader.
    ```

## Listed code blocks via fencing; language

*   *This is important*

    This code block is introduced with backtick fences and has a language tag.
    It is presented with a grey background that spans the whole text. It is
    subject to <https://github.com/quarto-dev/quarto-cli/issues/5538>

    ```default
    some code blocks are really long and do not know when to quit because they are presenting some information that was produced by some external tool and wrapping that text might change how it is interpreted by the reader.
    ```
````

### Expected behavior

Uniform treatment of code blocks without a language identifier.

### Actual behavior

Partial grey backgrounds.

### Your environment

- OS: macOS 12.6.6

### Quarto check output

```
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.1.1: OK
      Dart Sass version 1.55.0: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.3.353
      Path: /Applications/RStudio.app/Contents/Resources/app/quarto/bin

[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....OK
      Version: 3.9.6
      Path: /Library/Developer/CommandLineTools/usr/bin/python3
      Jupyter: (None)

      Jupyter is not available in this Python installation.
      Install with python3 -m pip install jupyter

[✓] Checking R installation...........OK
      Version: 3.6.3
      Path: /Library/Frameworks/R.framework/Resources
      LibPaths:
        - /Library/Frameworks/R.framework/Versions/3.6/Resources/library
      knitr: 1.42.8
      rmarkdown: 2.20

[✓] Checking Knitr engine render......OK
```
dragonstyle
2023-06-02T13:39:33Z
aronatkins
bug triaged-to
open
default code block background spans initially visible section, not whole text
https://github.com/quarto-dev/quarto-cli/issues/5789