Privacy policy

QFT.org is operated by Jie Ren. This notice explains what happens to information when you read the site, use its browser features, submit feedback, or send email. QFT.org does not require a reader account and does not use reader information for advertising.

Effective date: 12 September 2026.

Data generated when you visit QFT.org

QFT.org is a static site delivered through Cloudflare Pages and Cloudflare’s content-delivery and security network. When your browser requests a page or file, Cloudflare processes ordinary connection and request information needed to deliver, cache, secure, and troubleshoot the site. This can include your IP address, the date and time, the requested address, HTTP headers such as browser type and referring site, and network, TLS, and security information.

Cloudflare may also ask supporting browsers to send Network Error Logging reports when a connection fails. These reports concern network delivery; they do not contain feedback-form entries. Cloudflare describes its handling of service and security data in the Cloudflare Privacy Policy. Cloudflare operates a global network, so this processing can occur in more than one country.

QFT.org enables Cloudflare Web Analytics for visitors in all regions to understand page use and improve site performance. QFT.org does not use Google Analytics or advertising trackers.

The analytics service runs a JavaScript beacon in your browser and sends usage and performance measurements to Cloudflare. These include page and referring addresses, browser and device categories, country, page-loading times, responsiveness, and layout shifts. Cloudflare describes these measurements in its Web Analytics dimensions and Core Web Vitals documentation.

According to Cloudflare, its analytics beacon does not use cookies or browser storage and does not fingerprint individual visitors. Its analytics endpoint receives your IP address as part of the request, discards it at the nearest Cloudflare data center, and does not store it in the analytics core databases or logs. Analytics processing may occur outside your country. See Cloudflare’s RUM data processing and privacy information. The infrastructure and security processing described above still applies.

Search, browser storage, and external links

The main site search uses a static Pagefind index. A search term is processed in your browser, which downloads same-origin index and result files; it is not sent to an external search provider. Queries on the dedicated search page and filters in the reference catalog can appear in the page address. If you reload, bookmark, or share such an address, that text can appear in browser history and in ordinary request logs.

The site stores two interface preferences in your browser:

• starlight-theme in local storage records the light, dark, or automatic color-theme choice and remains until you change it or clear site data.
• sl-sidebar-state in session storage records sidebar expansion and scroll position for the current browser tab and normally ends with that tab’s session.

QFT.org does not transmit these preferences. It does not use its own cookies for these settings. Cloudflare may use strictly necessary security cookies when it challenges suspicious traffic.

Links to papers, databases, and other websites are ordinary external links. When you follow one, the destination receives a request and applies its own privacy policy.

Feedback form and spam protection

Opening the Send feedback page loads Cloudflare Turnstile from challenges.cloudflare.com. Turnstile examines limited browser and connection signals—including IP address, TLS fingerprint, user-agent header, site key, and site origin—to distinguish likely people from automated traffic. Cloudflare does not receive the feedback message or optional email address through the Turnstile widget. Its use of these signals is described in the Turnstile Privacy Addendum. Turnstile pre-clearance is disabled, so the widget is not configured to issue a cf_clearance cookie.

When you submit the form, QFT.org’s Worker at adscft.org verifies the one-time Turnstile token and stores this record in Cloudflare Workers KV:

• your message;
• the email address you provide, if any;
• the allowed site origin; and
• the submission time.

The stored feedback record does not include your IP address, user agent, honeypot field, or Turnstile token. The Worker does not read CF-Connecting-IP and does not send an IP address to Turnstile’s verification endpoint. Cloudflare still processes request metadata as the Worker provider. Invocation logging is enabled on the current Workers Free plan; those logs are retained for three days under Cloudflare’s Workers Logs limits. The Worker does not write feedback contents to those logs.

Feedback is used to investigate and respond to scientific or editorial errors, accessibility barriers, security or rights concerns, and suggestions about the site. If you provide an email address, Jie Ren may use it to reply about that submission. Only Jie Ren is authorized to view stored feedback.

Email

Mail sent to [email protected] is forwarded by Cloudflare Email Routing to a Microsoft-hosted MSN mailbox. Cloudflare processes the message in transit, and Microsoft stores it in the destination mailbox. Only Jie Ren has access to that mailbox. Microsoft’s processing is described in the Microsoft Privacy Statement.

Retention, deletion, and location

Information	Location	Current retention
Theme preference	Your browser’s local storage	Until changed or cleared
Sidebar state	Your browser’s session storage	Normally until the tab session ends or the data is cleared
Cloudflare infrastructure and security data	Cloudflare systems	According to Cloudflare’s applicable service and privacy policies
Web Analytics measurements	Cloudflare Web Analytics	Cloudflare documents seven days of unsampled data followed by aggregated storage, with six months of accessible history; see its Web Analytics FAQ
Worker invocation logs	Cloudflare Workers Logs	Three days on the current Free plan
Feedback records	Cloudflare Workers KV	No automatic expiration is currently configured; records remain until Jie Ren deletes them
Email and replies	Cloudflare Email Routing and the destination Microsoft mailbox	Remain in the mailbox until manually deleted, subject to the providers’ own retention obligations
Turnstile signals	Cloudflare	According to the Turnstile Privacy Addendum and Cloudflare Privacy Policy

The feedback KV namespace has no jurisdiction restriction. Cloudflare therefore replicates it across its global network, as explained in the Workers KV data-location documentation. QFT.org does not intentionally collect sensitive personal information through the form; please do not submit passwords, private keys, unpublished results, or other confidential material.

Your choices and requests

You can read and search QFT.org without submitting the feedback form or giving QFT.org your email address. You can clear the theme and sidebar values through your browser’s site-data controls. You can also contact QFT.org by email instead of using the form, although that email will be processed by Cloudflare Email Routing and Microsoft.

You can use browser content-blocking tools to block the analytics beacon, as described in Cloudflare’s Web Analytics FAQ. Ordinary delivery and security processing still occurs when you request the site.

To ask what identifiable information QFT.org holds about you, correct it, or request deletion, email [email protected]. If you submitted feedback without an email address, include enough non-sensitive detail—such as the approximate submission date and a short excerpt—to locate the record. QFT.org may be unable to identify a fully anonymous submission.

Contact and changes

Jie Ren is the operator and privacy contact for QFT.org. Send privacy questions or requests to [email protected].

This notice will be revised when a material data flow, processor, retention practice, or reader choice changes. The effective date above will be updated with the revision.