Why We Built an In-Browser Screenshot Redactor with Zero Server Uploads

Sharing screenshots during code reviews, bug reports, Discord chats, or customer support often exposes sensitive data: API tokens, bearer keys, and PII.

Many developers default to using translucent marker pens on mobile or uploading images to third-party cloud redactors. Unfortunately, brightness-curve adjustments and automated de-blurring tools like Depix can reverse partial blur or translucent marks. Furthermore, uploading confidential screenshots to remote servers is a security risk.

To solve this, I built Bluro (https://bluro.pro) - a fast, 100% client-side privacy tool:

Key Technical Pillars

1. Zero Cloud Uploads: Built entirely with HTML5 Canvas API and GPU acceleration directly in memory. Images never touch a remote server, ensuring complete data sovereignty. It even works completely offline.
2. Solid Blackout Mode: Permanent mathematical pixel occlusion (#000000), completely immune to de-blurring or contrast recovery exploits. Also supports adjustable Gaussian blur and pixelation when aesthetic masking is preferred.
3. Fast Clipboard Workflow: Paste screenshots directly with Cmd+V / Ctrl+V, drag bounding boxes across sensitive tokens, and copy out via the Async Clipboard API in under 5 seconds.
4. Text Redaction & Censor Bars: Includes a dedicated Redacted Text Generator for copy-pasting unicode blackout bars, plus transparent black censor bar PNGs for video editing.
5. Cross-Platform Markdown Spoilers: 1:1 Discord chat bubble emulator with click-to-reveal masks, plus translation to Reddit and Telegram.

The project is built with Next.js static export and hosted on Cloudflare Pages.

Try it out here: https://bluro.pro (or the Screenshot Redactor directly). Feedback, bug reports, and suggestions are warmly welcome!