The DiagnoSEO browser extension for Chrome and Firefox is built to be privacy-first. This section explains exactly how it handles data.

What the extension accesses. When you click the DiagnoSEO icon on a page you want to analyze, the extension reads that page’s publicly available content directly inside your browser: the HTML source, meta tags, headings, links, images, structured data, and the page’s HTTP response headers (such as the status code, X-Robots-Tag, and canonical). To check redirect chains and response headers, it observes the navigation requests of the tab you are analyzing.

What the extension does NOT do. The extension does not collect, store, or transmit your browsing activity, page content, or personal information to DiagnoSEO servers or to any third party. It contains no analytics, tracking, advertising, or fingerprinting. It does not sell or share data, and it does not build a user profile or track you across websites.

Network requests. The only network requests the extension makes are to the same page you are analyzing — to retrieve that page’s HTML, favicon, response headers, and (for the GEO/AI checks) its /llms.txt file. These requests are made without your cookies or credentials. No data is sent to DiagnoSEO or to any external server.

Data storage and retention. All analysis happens locally in your browser and is ephemeral — it is held in memory only while the popup is open. The extension stores no analysis results and keeps nothing after you close it.

Permissions and why they are needed.

activeTab and scripting — to read and analyze the page you actively choose to inspect.
tabs — to read the current tab’s URL and title so the analysis can run.
webRequest — to observe the analyzed page’s navigation in order to detect redirect chains and read SEO-relevant response headers. This is observation only; the extension does not block, modify, or redirect any request.
host access (all sites) — so you can analyze any page you visit. This access is only used when you actively trigger an analysis.
Contact. For privacy questions about the extension, contact us at support@diagnoseo.com