OpusPad icon

OpusPad

by support@dull.business · Developer Tools
Manifest V3 Free
View in Chrome Web Store Data as of 16 Oct 2026

Review and edit local Markdown files in Chrome. WYSIWYG + source mode. 100% private, zero uploads. Built for AI-indigenous builders.

Users
20
0 in 30 days
Rating
0.0 / 5
unchanged in 30 days
Ratings
0
0 in 30 days
Store rank
#152K
#126K among extensions
Version
1.3.1
updated 31 May 2026

Users

monthly, 7 months
01021Mar 2026Jul 2026Oct 2026
Latest, 16 Oct 2026: 20 usersMove the mouse over the chart for any month

Ratings count

monthly, 7 months
001Mar 2026Jul 2026Oct 2026
Latest, 16 Oct 2026: 0 ratingsMove the mouse over the chart for any month

The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.

About OpusPad

HOW TO USE: Open OpusPad by clicking its icon in your browser toolbar, then click 'Open Folder' to select your project directory and start editing. In AI-assisted development, specs are no longer optional notes—they are working artifacts. Agents read specs, generate plans, update task lists, and write implementation notes. Spec-driven development only works if those files stay readable and editable. Agents can draft the code, but humans still need to inspect, refine, and trust the artifact. OpusPad sits in the sweet spot for this review loop: it’s a browser-native, local-first editor purpose-built for reading and editing the Markdown files already in your repository. KEY FEATURES: • WYSIWYG Editor — Review specs and generated plans without the overhead of raw Markdown noise. Tables, code blocks, and lists render cleanly. • Source Mode — Drop down to raw Markdown for precise edits when structure and document formatting matter. • External Change Detection — When an AI agent updates your project tracker or CLAUDE.md on disk, OpusPad detects the change and reloads instantly to keep you in sync. • Local File Access — Work directly with your repo artifacts. Read and write directly using Chrome's native File System API. • Auto Save — Your edits persist to disk automatically. Refine a spec and your agent immediately sees the updated file. • Directory Sidebar — Browse your project's spec folders. Smart fuzzy search lets you jump between design docs and implementation notes instantly. • 100% Local & Private — Your sensitive specs and proprietary code never leave your machine. Zero telemetry, zero cloud sync, zero data collection. • Lightweight — Optimized for quick review loops, not general note-taking fluff. Runs natively inside Chrome without Electron overhead. PERFECT FOR: - Writing and refining architecture specs - Reviewing agent-generated plans and task files - Editing implementation notes and CLAUDE.md rulesets seamlessly - Keeping everything strictly local and repo-native

Growth

WindowUsersChangeRatingsRating
7 days−1−4.8%00.00
30 days0+0.0%00.00
6 months+10+100.0%00.00

Version history

7 versions recorded
1.3.131 May 2026
1.316 Apr 2026
1.2.224 Mar 2026
1.2.117 Mar 2026
1.216 Mar 2026
1.114 Mar 2026
1.012 Mar 2026

Details

Category
Developer Tools
First seen
12 Mar 2026
Size
1.2 MB
Languages
en-US
Pricing
Free
Support
editor.dull.business
Extension ID
ephlhjlnpnjjnjgdohdnbknadhklcoag

Permissions and risk

Minimal riskimpact 0, likelihood 2

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