For the last few months I've been building Screen Studio — a Chrome extension that captures screenshots, records your screen, and lets you edit and export videos without ever sending a single byte to a server.
No backend. No account. No tracking. No cloud upload. Everything happens locally on your own machine.
In this post I'll walk you through every feature, show you the actual UI, and explain the one thing most people get wrong about browser extensions: where your files are really stored.
It's completely free, and I'd genuinely love your feedback before the final release. 🙏
🎯 What It Does (in one line)
Capture screenshots, record your screen + webcam + mic, edit the recording on a real timeline, and export to PNG / JPG / PDF / WebM / MP4 / GIF — all offline.
Let me show you each part.
The Popup — Your Control Center
The moment you click the extension icon, you get everything in one clean panel.
Screen Studio popup UI — capture modes on top, screen recording options below.
Capture Modes:
📸 Visible Area — grab exactly what's on screen
✂️ Custom Region — drag-select any part of the page
📄 Full Page — captures the entire scrolling page, stitched into one tall image
Choose your format: PNG (lossless) or JPEG (smaller files)
Screen Recording — 4 sources:
🗂️ Tab — record just the current browser tab
🖥️ Screen — your entire desktop
🪟 Window — a single app window
🎥 Webcam — camera-only recording
Plus two toggles that make tutorials look professional:
🎙️ Microphone audio — narrate while you record
🎥 Webcam bubble — a draggable, circular camera overlay (great for classroom & YouTube tutorials)
Everything also has keyboard shortcuts — Ctrl+Shift+S for visible capture, Ctrl+Shift+F for full page, Ctrl+Shift+E for region, and Alt+Shift+V to start/stop recording.
The Screenshot Editor — Annotate Before You Share
After a capture, the screenshot opens straight into a full editor. No "save then open another app" — it's instant.
The editor: annotation tools on the left, live canvas in the center, layers panel on the right.
What you can do here:
✏️ Draw, arrow, rectangle, circle, line to point things out
🔤 Add text labels
🌫️ Blur / pixelate sensitive info (passwords, emails, tokens)
✂️ Crop to the perfect frame
🎨 Pick colors and stroke width
🗂️ Layers panel — every annotation is a separate, editable layer (non-destructive!)
↩️ Full undo / redo history
📤 Export to PNG, JPG, or PDF — or copy straight to clipboard
This is built on a real canvas engine, so your edits never bake into the image until you export. Change your mind anytime.
The Vault — Your Private Local Library
Every screenshot and recording is saved into the Vault — a searchable library that lives inside your browser, on your disk.
The Vault: storage meter at the top, searchable grid of all your captures below.
Features:
🔍 Search by name or date
🏷️ Filter by Screenshots / Videos / All
↕️ Sort by date
📊 A live storage meter so you always know how much space you're using
▶️ Click any video to jump into the editor
And here's the important part most people don't know about 👇
💾 Where Are Your Files Actually Stored? (The Honest Answer)
This is the part I'm most proud of, because it's where privacy and performance meet.
Your captures are not saved to some company's cloud. They're written to IndexedDB, which the browser stores on your local SSD/hard drive. That's why everything is instant and works even with zero internet.
But here's the nuance between browsers:
🟢 On Chrome
Chrome reports your real, available disk space. If you have 200 GB free on your SSD, the extension can use a big chunk of that. You can record long sessions and store dozens of videos. Your hardware is the only real limit. As a runaway-capture safety rail, a single recording is capped at 2 hours.
🔵 On Brave
Brave does something clever for privacy / anti-fingerprinting: it fakes the storage quota at a fixed ~2 GB for every site, no matter how big your actual drive is. Websites can't probe your real disk size to identify you.
That's great for privacy — but it means the same recording that fits easily on Chrome can hit a wall on Brave. So Screen Studio detects Brave at runtime and adapts: it caps a single recording at 1 hour, so the take always saves cleanly to the Vault instead of dying mid-recording when the faked ~2 GB quota fills up.
TL;DR: Your files live on your SSD. Chrome gives you your full disk (2 h max per take). Brave protects your privacy by faking a ~2 GB cap — and Screen Studio detects it and stops cleanly at 1 h so you never lose a recording.
The Video Editor — Edit & Export Without Leaving the Browser
Recordings open into a proper, timeline-based video editor. This isn't a toy trimmer — it's a multi-track editor.
The recording editor: clip controls on the left, multi-track timeline at the bottom with video, audio, music, and overlay lanes.
What you can do:
⚡ Speed control — 0.5× to 2× playback
✂️ Split at playhead and trim clips
➕ Merge multiple videos together
🎵 Add background music (separate audio track with waveform)
🔇 Mute the original recorded sound
🔤 Text overlays that appear at chosen moments
🌫️ Blur overlays to hide sensitive info in the video
🎚️ Independent audio, music, and overlay lanes on the timeline
The export engine is the secret weapon:
Exports use WebCodecs (the modern, GPU-accelerated browser video API) via mediabunny — no ffmpeg, no WebAssembly bloat, no server round-trip
Export to WebM, MP4, or GIF
If you made no edits, WebM does a lossless passthrough — it hands back the original recording untouched, basically instant
Edited timelines re-encode locally (VP9/VP8 + Opus for WebM, H.264 + AAC for MP4) on your own GPU/CPU — your video never leaves your computer
🔒 Why "Offline" Actually Matters Here
A lot of extensions say "private" but quietly upload your data. Screen Studio is built so it physically can't:
✅ host_permissions is empty — it doesn't have blanket access to your browsing (full-page capture asks for access only on the tab you're on)
✅ A strict Content-Security-Policy blocks loading any external script
✅ connect-src is locked to local sources — no analytics, no phone-home
✅ No login, no account, no email required
If you're recording a classroom session, a client demo, or anything sensitive — it never touches the internet.
💸 The Price: Free
Right now, Screen Studio is 100% free. Every feature in this post — capture, annotate, blur, record, multi-track editing, MP4/WebM/GIF export, the Vault — all free, no paywall, no watermark.
🙏 I'd Love Your Feedback
I just submitted Screen Studio to the Chrome Web Store (v0.9.0, beta), and before the wider launch I want to hear from real developers and creators:
Would you use this for tutorials / bug reports / classroom recording?
What feature is missing that would make it a daily driver?
Anything confusing in the UI?
Drop a comment below — every bit of feedback helps me ship a better v1. 👇
If you build, teach, or report bugs for a living, this was made for you. Thanks for reading! 🚀
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