## What it does
Flags lines that end with one or more trailing space or tab characters. The exception is the
CommonMark hard-break convention: exactly two trailing spaces followed by a newline introduces
a `<br>` inside a paragraph, and that case is left alone.
## Why
Trailing whitespace is invisible noise that survives copy-paste, complicates diffs (one-byte
changes that touch every line), and frequently triggers spurious changes when collaborators
have different editor settings. The autofix strips the trailing run while preserving the
two-space hard break form.
## Example (bad)
```text
A paragraph.···
Another line.·
```
(`·` represents a stray trailing space.)
## Example (good)
```text
A paragraph.
Another line.
```
## Configuration
- Disable inline: `<!-- mdwright: allow trailing-whitespace -->`.
- Disable in config: `[lint] ignore = ["trailing-whitespace"]`.
- Severity: non-advisory. Safe autofix available.
## References
- [CommonMark §6.7: Hard line breaks](https://spec.commonmark.org/0.31.2/#hard-line-breaks).