browser-toolbox

A small Chrome extension I use as a personal browser toolbox. It collects tiny fixes and overrides that make everyday browsing less annoying.

No account, backend, analytics, or remote service.

Tools

• User agent: apply a per-tab User-Agent header profile, then reload the tab.
• Right click: keep Chrome's context menu available on sites that try to suppress it.
• Text viewer: replace Chrome's plain-text page with a readable viewer. Markdown files render as GFM; other text stays raw.
• Responsive width: scale fixed-width pages down for selected domains. Defaults to *.naver.com.
• Focus redirect: redirect distracting domains to https://www.keybr.com/. Defaults to x.com, youtube.com, and news.ycombinator.com.
• Keep note viewport: expand open Google Keep notes to the viewport with a 10 px edge gap.

Install

1. Open chrome://extensions.
2. Enable Developer mode.
3. Click Load unpacked.
4. Choose this repository folder.
5. Click the extension icon to open the side panel.

After source changes, reload the extension from chrome://extensions.

Notes

• Settings are stored in Chrome extension storage.
• User-agent changes affect only the active tab's top-level page request. They do not change Client Hints, cookies, JavaScript values, device metrics, subresources, or viewport size.
• Right-click and responsive-width features run on normal webpages and frames. Chrome extension scripts cannot run on internal pages such as chrome://.
• Local text files require Allow access to file URLs on the extension's Chrome details page.
• Markdown rendering uses bundled copies of Marked, DOMPurify, and highlight.js; it does not load executable code from a CDN.
• Responsive-width domain patterns are edited one per line in the side panel. Matching tabs may need a reload.
• Focus redirect applies to top-level page visits. A domain like youtube.com also matches subdomains like www.youtube.com.

Layout

assets/icons/      Extension icons
src/background.js  Extension lifecycle and message routing
src/features/      One module per browser-toolbox feature
src/shared/        Shared profiles, defaults, and setting keys
src/sidebar/       Side-panel UI
vendor/            Bundled Markdown rendering libraries and licenses
manifest.json      Manifest V3 entry point