---
epic: 10
story: 10.5
title: "Line Numbers"
status: draft
---

## Epic 10 — Notepad UX (Cross-Platform Spec)
**Goal:** Consistent editor behavior specified once, implemented per platform.

### Story 10.5: Line Numbers

As a user,
I want optional line numbers in the editor gutter,
So that I can reference specific lines when collaborating or reviewing.

**Acceptance Criteria:**

**Given** the user enables line numbers in settings
**When** the editor renders a sheet
**Then** a gutter column on the left displays sequential line numbers starting at 1
**And** the line numbers are rendered in a dimmed/muted color to avoid visual clutter

**Given** line numbers are enabled
**When** the user inserts or deletes lines
**Then** all line numbers update immediately to reflect the new sequence

**Given** line numbers are enabled
**When** the user toggles line numbers off in settings
**Then** the gutter column is hidden
**And** the input column expands to reclaim the gutter space

**Given** the user has toggled line numbers on or off
**When** they reopen the app
**Then** their line number preference is remembered and applied