https://github.com/rust-lang/rust/issues/133150
This is more likely to be intended as an intra-doc link than it is to be
intended as a refdef. If a refdef is intended, it does not need to be
nested within a list item.
```markdown
- [`LONG_INTRA_DOC_LINK`]: this
looks like an intra-doc link,
but is actually a refdef.
The first line will seem to
disappear when rendered as HTML.
```
> - [`LONG_INTRA_DOC_LINK`]: this
> looks like an intra-doc link,
> but is actually a refdef.
> The first line will seem to
> disappear when rendered as HTML.
changelog: [`doc_nested_refdefs`]: add suspicious lint for link def at
start of list items and block quotes