SupSub

SupSub is an Obsidian plugin that allows you to easily format selected text with <sup> and <sub> tags, enabling quick superscript and subscript formatting in your notes.

Usage

• Superscript:

  • Hotkey: Option + Command + '=' on macOS or Ctrl + Alt + '=' on Windows.
  • With selection: Wraps the selected text with <sup> tags.
  • Without selection: Activates superscript typing mode — a status bar indicator ("SUP") appears and everything you type is formatted as superscript. Press Escape to exit.
  • Button: Sup (ⁿ)

• Subscript:

  • Hotkey: Option + Command + '-' on macOS or Ctrl + Alt + '-' on Windows.
  • With selection: Wraps the selected text with <sub> tags.
  • Without selection: Activates subscript typing mode — a status bar indicator ("SUB") appears and everything you type is formatted as subscript. Press Escape to exit.
  • Button: Sub (ₙ)

• Remove Formatting:

  • Action: Removes existing <sup> or <sub> tags from the selected text.
  • Button: Normal (n)
  • With hidden tags: When the "Hide Tags" setting is enabled, simply select the visible superscripted/subscripted text and hold the modifier key — the "Normal (n)" button appears automatically, even if your selection doesn't perfectly match the raw tag boundaries.

• Toggling:

  • If the selected text is already wrapped in <sup> or <sub>, using the respective button or hotkey will remove the tags.
  • The plugin uses position-aware detection: as long as your cursor or selection overlaps any part of a tag, it will correctly unwrap instead of double-wrapping.

• Popup Modifier Key:

  • By default, the popup buttons only appear when holding Cmd (macOS) or Ctrl (Windows/Linux) while selecting text.
  • Change the modifier key in Settings > SupSub > Popup Modifier Key.
  • Set to None to restore the previous always-show behavior.

Example Workflow

1. Add Superscript/Subscript:

   • Select the text you want to format.
   • Click the Sup (ⁿ) or Sub (ₙ) button in the popup, or use the designated hotkeys.
   • The selected text will be wrapped with the corresponding tags, and the popup will disappear.

2. Remove Superscript/Subscript:

   • Select the text that is already formatted with <sup> or <sub> tags.
   • Click the Normal (n) button in the popup.
   • The tags will be removed, the text will be reverted to normal formatting, and the popup will disappear.

3. Remove Formatting with Hidden Tags:

   • With Hide Tags enabled, tags are invisible — you only see the styled content.
   • Select the visible superscripted/subscripted text and hold the modifier key (Cmd/Ctrl).
   • The popup shows Normal (n) — click it to remove the tags.
   • No need to select the exact raw tag boundaries; any overlapping selection works.

Contributing

Contributions are welcome! If you encounter any issues or have suggestions for improvements, please open a new issue or submit a pull request in the GitHub repository.

License

This plugin is licensed under the MIT License.

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Changelog

Version 1.1.1 (@2026-02-18)

• Bug Fixes:

  • Fixed Decoration Ordering Crash: Replaced RangeSetBuilder with Decoration.set(ranges, true) to eliminate "Ranges must be added sorted" console errors on edge cases.
  • Fixed Cursor Placement After Wrapping: After wrapping text with sup/sub, the cursor now correctly lands inside the tags (before the closing tag) instead of at the end of the line. Uses requestAnimationFrame to ensure stable positioning after decoration reflow.
  • Fixed Normal Button Not Appearing: When tags are hidden by decorations, selecting superscripted/subscripted content now reliably shows the "Normal (n)" button. Uses overlap detection instead of strict containment, so imprecise selections still work.
  • Fixed Double-Wrapping: Selecting text that partially overlaps existing tags no longer produces malformed output like <sup><sup>2</sup></sup>. The plugin detects overlapping tags and unwraps instead of double-wrapping.

• Improvements:

  • Position-Aware Unwrapping: The unwrap logic now scans the raw line for tags at the cursor position rather than relying on exact selection text. This handles all cases where hidden decorations cause visual-to-raw coordinate mismatches.
  • Cursor Line Tag Visibility: Tags are now shown on the line where the cursor is (matching Obsidian's native behavior for bold/italic), allowing direct editing when needed.

Version 1.1.0 (@2026-02-17)

• Bug Fixes:

  • Fixed Tag Hiding Rendering: Switched from Decoration.mark() with display: none to Decoration.replace() for hiding <sup>/<sub> tags. This eliminates cursor position mismatches that caused letters to disappear when typing near formatted text.
  • Fixed Text Shifting: Removed display: inline-block and position: relative CSS properties from superscript/subscript elements that were causing text to shift positions during editing.
  • Fixed Hide Tags Toggle: The "Hide Tags" setting now properly toggles on and off without requiring a restart.
  • Performance Optimization: Decoration computation now only processes visible ranges instead of the entire document.

• New Features:

  • Modifier Key for Popup: The popup buttons now require holding a modifier key (Cmd/Ctrl by default) while selecting text. This prevents accidental popup appearances during normal text navigation. Configurable in Settings with options: Cmd/Ctrl, Ctrl, Shift, Alt, or None (legacy behavior).
  • Toggle Typing Mode: Activate superscript or subscript mode without selecting text first. Place your cursor and press the hotkey — a status bar indicator appears and everything you type is automatically formatted. Press Escape to exit. Supports toggling between modes and auto-exits on line change.

Version 1.0.5 (@2025-05-19)

• Bug Fixes:
  • Fixed Text Shifting Issue: Resolved an issue where superscript and subscript text would shift positions when editing text in rows above.
  • Fixed Disappearing Text: Fixed a problem where letters would disappear when typing near superscript or subscript content.
  • Improved Decoration Handling: Enhanced the way hidden tags are managed to ensure consistent editing experience.

Version 1.0.4 (@2024-12-03)

• Bug Fixes:

  • Resolved Selection Error: Fixed an issue where enabling the popup buttons and using the Sup or Sub buttons could cause a TypeError related to invalid selection points. The plugin now correctly validates selection ranges to prevent errors.

• Improved Stability:

  • Enhanced compatibility with the latest Obsidian updates by refining editor integrations and ensuring seamless functionality.

Version 1.0.3 (@2024-12-01)

• Enhanced Button Labels: Updated the popup buttons to be more user-friendly:
  • Sup (ⁿ): Wraps the selected text with <sup> tags.
  • Sub (ₙ): Wraps the selected text with <sub> tags.
  • Normal (n): Removes existing <sup> or <sub> tags from the selected text.
• Conditional Button Display:
  • When the selected text is already wrapped in <sup> or <sub>, only the Normal (n) button is displayed to allow easy removal of the tags.
  • When the selected text is not wrapped, both Sup (ⁿ) and Sub (ₙ) buttons are available for formatting.