Please do not open a public issue for security problems. Report them privately:

• GitHub: Security tab › Report a vulnerability (private advisory), or
• Email: philipp@wornath.de

Include what you found, how to reproduce it, the browser and extension version (Settings › About). I aim to answer within a few days.

The extension (plugin/), the bookmarklet generator and the website (site-src/, docs/). Of particular interest:

• Anything that lets a web page or feed read the user's API keys, license key, history or highlights.
• Script injection through page-, feed- or model-derived content (summaries, titles, tags, recaps).
• The messaging between the content script, the in-page sidebar and the extension (sidebarChannel.js, EXTENSION_PAGE_ACTIONS in background.js).
• Prompt injection that makes the extension take an action the user did not ask for.

The byPhil backend (api.byphil.eu) is a separate service; reports about it are welcome at the same address.

• API keys and the license key stay in chrome.storage.local and are never synced.
• Content from pages and feeds is escaped or cleaned before it is rendered (textUtils.js: escapeHtml, cleanUntrustedHtml).
• Background actions that spend the AI key or fetch for the extension refuse content scripts.