# CJK Bold Fix

An [Obsidian](https://obsidian.md) plugin that fixes **bold** and *italic* rendering for CJK (Chinese, Japanese, Korean) text in Live Preview mode.

## The Problem

Obsidian's Live Preview (editing mode) uses CodeMirror 6, which follows the CommonMark specification for emphasis parsing. The CommonMark spec's "left-flanking" and "right-flanking" delimiter run rules were designed for space-separated languages like English and break when CJK punctuation appears adjacent to emphasis markers.

### Examples of broken patterns

```markdown
は、**知識があれば**です。       ← Doesn't render as bold
**テスト。**テスト              ← Doesn't render as bold
これは**重要な**テキストです     ← Doesn't render as bold
```

> **Note**: Reading mode (preview) renders correctly — the bug only affects Live Preview (editing mode).

This is a [known CommonMark issue (#650)](https://github.com/commonmark/commonmark-spec/issues/650) with 235+ comments, unresolved for 7+ years.

## How It Works

The plugin registers a CodeMirror 6 ViewPlugin that operates in 4 phases:

1. **Collect parser emphasis** — Reads HyperMD syntax tree to find where the parser applied bold/italic
2. **Find correct emphasis** — Uses per-line regex to determine where `**...**`, `*...*`, and `***...***` patterns with CJK content should actually be
3. **Override wrong emphasis** — Applies `font-weight: normal` to ranges the parser incorrectly bolded
4. **Apply correct emphasis** — Adds bold/italic styling and hides `**`/`*` markers where the parser missed

## Installation

### From Community Plugins

Search for "CJK Bold Fix" in Obsidian's Community Plugins browser.

### Manual Installation

1. Download `main.js` and `manifest.json` from the [latest release](https://github.com/ebibibi/obsidian-cjk-bold-fix/releases)
2. Create a folder `cjk-bold-fix` in your vault's `.obsidian/plugins/` directory
3. Copy the files into that folder
4. Enable the plugin in Obsidian's settings

## Supported Languages

- Japanese (Hiragana, Katakana, Kanji)
- Chinese (Simplified & Traditional)
- Korean (Hangul)

## Technical Details

- **Approach**: ViewPlugin + Decoration (no monkey-patching, no internal API dependencies)
- **Performance**: Only processes visible ranges, rebuilds only on document/viewport/selection changes
- **Compatibility**: Uses only official Obsidian plugin APIs (`registerEditorExtension`)
- **Emphasis types**: Bold (`**`), italic (`*`), and bold+italic (`***`)

## Related

- [CommonMark Issue #650](https://github.com/commonmark/commonmark-spec/issues/650) — The upstream specification issue
- [Obsidian Forum Discussion](https://forum.obsidian.md/t/parsers-problems-with-bold-italic-highlight-markers-and-whitespaces-and-punctuation-marks/105107)
- [markdown-cjk-friendly](https://github.com/tats-u/markdown-cjk-friendly) — Spec-level fix for various parsers

## License

MIT