Word highlighting breaks in special cases

[ben519]

Check out this example 👇 (It should highlight four characters in total, but it only highlights two of them.)

```shell showLineNumbers title="transformations" /r/1 /b/1 /c/3,6
raccoon -> baccoon # (1)!
baccoon -> babcoon # (2)!
babcoon -> baboon  # (3)!
```

Here's what this looks like rendered. Notice how the cs are not highlighted

... but if I simplify the Markdown to this

```shell showLineNumbers title="transformations" /c/3,6
raccoon -> baccoon # (1)!
baccoon -> babcoon # (2)!
babcoon -> baboon  # (3)!
```

the cs are highlighted.

Is this user error or a bug?