Privacy Policy

What MV3 Extension Dev Hub collects, what it does not, how the site is hosted, and the choices available to readers — written for a static documentation site with no accounts.

Published July 25, 2026 Updated July 25, 2026 8 min read
Table of Contents

This policy describes what happens to information when you read MV3 Extension Dev Hub. It is deliberately specific rather than generic: this is a static documentation site with no accounts, no comment system and no advertising, and the policy says so plainly instead of reserving rights the site does not exercise.

If you only read one section, read What we do not collect — for most visitors it is the whole answer.

Who runs this site

MV3 Extension Dev Hub is an independent technical documentation site about browser extension development. It is published as a set of static files: HTML, CSS, JavaScript and images, generated ahead of time and served directly. There is no application server, no database of readers and no login.

Questions about this policy can be sent to the contact address published on the site. Because there are no accounts, there is generally no stored record for us to look up in response to a request — which is itself the point of the design.

What we do not collect

Being explicit about absences is more useful than a list of possibilities:

  • No accounts. There is nothing to register for, so there are no names, email addresses or passwords.
  • No advertising or advertising networks. No third-party ad scripts run on any page, so no advertising profile is built from your reading.
  • No tracking pixels or social widgets. Pages do not embed like buttons, share widgets or beacons that report your visit to another company.
  • No cross-site tracking cookies. The site sets no cookies for analytics or advertising purposes.
  • No comment system. There is nowhere on the site to submit text, so no user-submitted content is stored.
  • No newsletter list. The site does not collect email addresses for mailing.
  • No fingerprinting scripts. The JavaScript that ships with each page handles the theme toggle, code-block copy buttons, the FAQ accordions and diagram controls. None of it profiles your browser or device.
What this site collects, and what it does notCategories of data a website might collect, whether this site collects them, and where any such data ends up.CategoryCollected here?Where it goesAccount detailsNoThere are no accountsAnalytics eventsNoNo script is includedAdvertising identifiersNoNo ad networkTracking cookiesNoNone are setTheme preferenceYesYour browser onlyRequest logsBy the hostCDN, short retention
Only the bottom two rows have anything in them, and neither leaves the browser or the host.

What is stored in your browser

Two small pieces of state are kept locally, in your own browser, and are never transmitted to us or to anyone else:

  • Your theme choice. When you use the light or dark toggle in the header, the choice is written to localStorage under a single key so the site opens in the theme you picked. Before you make a choice, the site follows your operating system’s own light or dark preference and stores nothing at all.
  • Ordinary browser caching. Your browser caches pages, stylesheets and images as it does for any website, according to the caching headers the host sends.

You can clear both at any time through your browser’s own settings for site data. Clearing the theme key simply returns the site to following your system preference. Nothing else is stored, and no functionality depends on storage being available — the site works normally with site data blocked.

Server logs and hosting

The site is served through a content delivery network. Like every web host, it processes the technical information your browser sends in order to deliver a page: the requested URL, your IP address, the user-agent string, the referring page if your browser sends one, and the time of the request. This is standard request handling rather than a feature of this site, and it is the minimum a server needs in order to return a response to the right place.

These logs are used for delivering content, keeping the site available and protecting it from abuse such as denial-of-service traffic. They are not used to build reader profiles, they are not sold, and they are not combined with any other data set — because no other data set exists. Retention is handled by the hosting provider under its own policies, which are typically measured in days to weeks for raw request logs.

Everything your browser sends when you open a pageA page request reaches the content delivery network and returns static files; a separate request fetches the web font from Google. Nothing else leaves the browser.Your browsera page requestContent delivery networkURL, IP, user agentStatic files returnedHTML, CSS, JS, SVGone further request, for the web fontGoogle Fontsgoverned by Google's policyNo other destinationno trackers, no embeds
Two destinations in total, and neither receives anything beyond an ordinary HTTP request.

Analytics

The site is built with an analytics integration that is switched off. No analytics script is included in the pages you receive, and no page-view events are sent anywhere.

If that changes, this policy will be updated before the change is deployed, this section will describe exactly what is collected, and the choice will favour aggregate, cookie-free measurement over per-visitor tracking. In the meantime, the honest statement is that we do not know how many people read any given page beyond what the host’s own request counts show.

Fonts and other third-party resources

Pages reference a web font served from Google Fonts. When your browser loads that font, it makes a request to Google’s servers, and that request carries the usual technical information described above — most relevantly your IP address and the page that requested the font. That request is governed by Google’s privacy policy rather than by this one.

No other third-party resource is loaded. Diagrams are inline SVG generated at build time, code highlighting happens at build time, and the small amount of JavaScript on each page is served from the same origin as the page itself. There are no third-party scripts, iframes, video embeds or trackers.

Pages link to browser vendor documentation, specifications, package registries and similar resources. Those sites have their own privacy practices, and following a link takes you outside the scope of this policy. Links are plain anchors: the site does not use redirect trackers or link-wrapping services, so following a link does not first report the click to us.

Children

The site is technical documentation aimed at software developers. It is not directed at children, and because it collects no personal information from anyone, it collects none from children either.

Where anything related to your visit actually livesYour theme choice stays in your browser, request logs sit with the hosting provider, and the site itself holds no reader records at all.Your browsertheme key, ordinary cacheclear it any timeHosting providerstandard request logstheir retention policyThis sitestatic files onlyno reader database existsThird partiesthe web font requestno trackers, no ad networks
There is no layer in this stack under our control that contains reader data — which is why most data requests have nothing to act on.

Search on this site

The site includes a search page. Search runs entirely in your browser against an index shipped with the site — the query is not sent to a server, is not logged and is not used to build a profile of what you were looking for. If search is ever moved to a hosted service, this section will say so and will name the service before the change is deployed.

Reporting a security problem

If you find a security issue with the site itself — a misconfiguration, a way to inject content into a page, an exposed file that should not be published — report it to the contact address on the site. Reports are welcome, and reporting one in good faith is explicitly not a breach of the terms of use. Please do not test availability by generating load.

Your choices and rights

Because the site holds no personal data about readers, the usual data-subject requests — access, correction, deletion, portability — have nothing to operate on here. That is not a way of declining them; there is genuinely no reader record to produce. The practical controls available to you are:

  • Blocking storage. The site works fully with site data disabled; you lose only the persistence of your theme choice.
  • Blocking third-party requests. Blocking the font request changes the typeface and nothing else. All content and functionality remains.
  • Using tracking protection. Browser tracking protection and content blockers have nothing to block on these pages, and none of them are detected or worked around.

For the request logs held by the hosting provider, requests should be directed to that provider, since they are the controller of that data in practice.

Changes to this policy

If this policy changes, the modified date at the top of the page changes with it, and material changes — particularly any that introduce analytics or a third-party script — will be described in the section they affect rather than summarised vaguely. Because the site is published from a version-controlled repository, the history of this document is part of the site’s own change history.

Summary

No accounts, no analytics, no advertising, no tracking cookies and no third-party scripts beyond a web font. One key in localStorage remembers whether you prefer the light or dark theme. Your browser’s requests reach a CDN, which logs them the way every web server does, and nothing further is done with them.

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