Better Heading Hierarchy

An Obsidian plugin that draws vertical guide lines beside your notes, so the nesting of Markdown headings is visible at a glance — the way indent guides work in a code editor.

Long notes flatten out visually: an ### three screens below its ## looks identical to a top-level one. This plugin colors and connects that structure instead of making you infer it from # counts.

Features

• Guide lines for every heading level. Each level from # to ###### gets its own color, and each block of content is indented to sit beside the line of the heading that owns it.
• Works while you edit and while you read. Reading view and the editor (Live Preview and Source mode) are rendered by separate engines; both are supported, and each can be turned off on its own.
• Handles messy documents. Skipped levels (# straight to ###), setext headings, and # lines inside code, math, comments, HTML, lists or frontmatter are treated the way Obsidian does.
• Runs through tables, callouts, math and embeds in both views, at the right indent.
• Fully restyleable. Colors, spacing and line thickness are CSS variables — no forks or !important battles needed. See Customizing the look.

Installation

From Obsidian (recommended)

Settings → Community plugins → Browse, search for Better Heading Hierarchy, then install and enable it. Or open the plugin page and click Add to Obsidian.

Manually

Download main.js, manifest.json and styles.css from the latest release and place them in <your vault>/.obsidian/plugins/better-heading-hierarchy/, then reload Obsidian and enable the plugin.

Settings

Guide lines

A single note can opt out with a heading-guides: false property, or opt back in inside an excluded folder with heading-guides: true.

Recommended styling

A button that writes snippets/rogers-theme.css into .obsidian/snippets/ and turns it on. It always shows where things stand and what pressing it will do, so it never rewrites a file behind your back:

Install on startup (off by default) puts the file back if it goes missing. It never overwrites a snippet you have edited.

Customizing the look

Everything visual is a CSS variable defined on body. To change any of it, create a CSS snippet and override the variables you care about — updates to the plugin will not overwrite your changes.

A separate, slightly darker color ramp applies under body.theme-light; a plain body { … } rule in your snippet overrides either.

For example, to get wider spacing and a monochrome accent-colored set of lines:

body {
  --rgh-indent: 16px;
  --rgh-content-gap: 22px;
  --rgh-line-width: 2px;
  --rgh-color-1: var(--color-accent);
  --rgh-color-2: var(--color-accent);
  --rgh-color-3: var(--color-accent);
  --rgh-color-4: var(--color-accent);
  --rgh-color-5: var(--color-accent);
  --rgh-color-6: var(--color-accent);
}

The author's theme snippet

The screenshot above is not what the plugin looks like on its own — it also uses my personal styling: neon heading text against the muted guide lines, equal-sized headings, a tighter vertical rhythm, a wider centered page, and custom fonts. Up to version 1.x that styling was bundled into the plugin behind an additional author-styled CSS toggle. It is now a plain CSS snippet instead, because it is a matter of personal taste rather than plugin behavior.

The plugin writes it to .obsidian/snippets/ and turns it on the first time it loads. To go without it, turn off rogers-theme under Settings → Appearance → CSS snippets. If the file goes missing, press Install and enable under Companion snippet in the plugin's settings. Once installed the file is yours — edit it freely, the plugin will not overwrite your changes unless you explicitly ask it to.

It is written for the default Obsidian theme in dark mode, and every section of it is commented and safe to delete piece by piece. Its page width works through Obsidian's own --file-line-width, so Readable line length needs to be on for the width cap and centering to apply. It leaves the guide lines at the plugin's default colors and only recolours the heading text; the comment at the top of the file says how to tint the lines to match.

If you want it to look exactly like the screenshot, install the fonts it asks for:

The snippet degrades gracefully: without these fonts it falls back to your theme's fonts and everything else still applies.

[!NOTE] Upgrading from 1.x? If you had additional author-styled CSS enabled, that setting is gone. Install the snippet above to get the same appearance back. The guide lines themselves are unaffected, and now also render while you edit.

How it works

Both views share one scan of the note's text that records, per line, how many guide lines it gets and whether it is a heading. It follows Obsidian's own parser and costs about 2 ms for a 20,000-line note.

• Reading view uses a Markdown post-processor. Each block reports its line range and the text it was rendered from, so its depth never lags behind an edit; one absolutely positioned element per guide line is inserted. Obsidian reuses blocks whose markup did not change, so the plugin also refreshes them when a heading above them changes. A table's horizontal scrolling is moved to an inner wrapper so the block stays a plain box.
• The editor insets each row by its depth — a .cm-line through a line decoration, a block widget (table, callout, math, embed) through a class on its DOM, since decorations cannot reach it — and draws the guide lines on a CodeMirror layer beneath the text, one rectangle per unbroken run of rows, so nothing in a row's own DOM can clip or move them. The inset is a transparent left border: Obsidian sets padding-inline-start inline on list lines and forces every line to zero margin.

Installing the companion snippet writes a file through Obsidian's public vault API. Enabling a snippet has no public API, so that step uses an internal one; if it is ever removed, the file is still written and the settings tab tells you to switch it on yourself.

The plugin makes no network requests. The one link it can open is the Open documentation button in its settings, which hands this readme's URL to your browser.

Known limitations

• Notes embedded in another note (![[Note]]) are not decorated: Obsidian does not expose the source line range for embedded content, which is what the plugin needs to place the lines.
• Guide lines follow the rendered block structure, so content inside a table cell or a callout is drawn relative to the block as a whole rather than per line.
• In the editor, a table wider than the page scrolls inside Obsidian's widget, so its cells slide under the guide lines while scrolled.

Related

Also by me: Recursive Fold, which folds or unfolds a heading together with everything nested under it, in one click.

Contributing

Bug reports and pull requests are welcome — see CONTRIBUTING.md for how to build the plugin and test it against a vault.

License

MIT © rogerfan48