ClearOnStart

A Chrome extension that clears your browsing history, cache, downloads, and form data the moment Chrome opens. No accounts, no telemetry, no surprises.

Why

Most "clear on exit" extensions miss too much: they rely on the chrome.windows.onRemoved event, which MV3 service workers are not guaranteed to fire before the worker is terminated. ClearOnStart hooks into chrome.runtime.onStartup instead, which is the only reliable startup trigger in MV3.

What it clears

Four categories, all essential, nothing more:

• Browsing history
• Cached images and files
• Download records
• Autofill form data

Features

• On-start wipe — runs automatically when Chrome launches.
• Manual clear — Clear now button in the popup.
• Time range — last hour, day, week, month, or forever.
• Per-category toggle — disable any of the four in settings.
• Manual save — changes in the settings page stay unsaved until you press Save. A pulsing red Save ● button and a browser warning on close keep you from losing work.
• Activity log — last 30 wipes with timestamp, trigger, and result.
• Dark mode — follows the system, with a manual override.
• Native notifications — off by default, opt in if you want a desktop ping after each wipe.
• Zero data exfiltration — no remote endpoints, no analytics, no sync.

Screenshots

Installation

Step 1 — Download the extension files

You need the extension files on your computer. Choose one method:

Option A — Download ZIP (easiest)

1. Go to the ClearOnStart Releases page.
2. Download the latest ClearOnStart.zip file.
3. Find the downloaded .zip file (usually in your Downloads folder).
4. Right-click the file → Extract All... → click Extract.
5. A new folder will appear — keep this folder, you'll need it in Step 3.

Step 2 — Open Chrome Extensions page

1. Open Google Chrome.
2. In the address bar at the top, type chrome://extensions and press Enter.
3. You'll see the Extensions management page.

Step 3 — Enable Developer mode

1. Look at the top-right corner of the Extensions page.
2. Find the toggle labeled Developer mode.
3. Click it to turn it ON (the toggle should turn blue).

Step 4 — Load the extension

1. After enabling Developer mode, new buttons appear at the top-left.
2. Click the Load unpacked button.
3. A file browser window opens. Navigate to the folder you extracted/downloaded in Step 1.
4. Select the folder (the one containing manifest.json), then click Select Folder.

Step 5 — Pin to toolbar (optional, recommended)

1. The ClearOnStart card now appears on the Extensions page.
2. Look for the puzzle piece icon (🧩) in Chrome's top-right toolbar.
3. Click it → find ClearOnStart → click the pin icon (📌) next to it.
4. The ClearOnStart icon now stays visible in your toolbar.

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The extension icon appears in the toolbar. Click it to open the popup, or right-click for the menu.

Troubleshooting

• "Failed to load extension" — Make sure you selected the correct folder (the one that contains manifest.json).
• Want to remove it? — Go to chrome://extensions, find ClearOnStart, and click Remove.

How it works

The service worker listens for chrome.runtime.onStartup. When Chrome starts, it reads the user's preferences (which categories, what time range), calls chrome.browsingData.remove(), and writes a row to the local activity log.

Settings are stored in chrome.storage.sync (preferences) and chrome.storage.local (activity log). The popup and options page read directly from these stores — there is no in-memory cache to keep in sync.

Privacy

ClearOnStart only calls the standard chrome.browsingData API. It does not:

• Contact any remote server.
• Read your browsing data (it only deletes it).
• Track you, fingerprint you, or store anything off your machine.

The only persisted data is your settings and the activity log, both local to your browser.

Credits

Built on top of the Chrome Extensions MV3 platform. Fonts by IBM Plex.