Privacy policy
LumensOS is a browser extension that changes how websites look on your device. We designed it so that it needs to know almost nothing about you. This page explains exactly what is and isn’t collected.
Chrome Web Store Limited Use
Personal and sensitive data that the extension collects or transmits is used only for the user-facing features described in this policy. We do not sell it, use it for advertising, or use it to determine creditworthiness or lending eligibility. We share it only with service providers as needed to operate those features, or when required by law. Our use and transfer of this data comply with the Chrome Web Store User Data Policy, including its Limited Use requirements.
What the extension does on your device
- It reads page styles to recolour them locally. We do not send your general browsing history to our servers. Audit page content is sent only if you choose to save or upload a full report; the other audit and account data flows are described below.
- Your settings (theme, colour-vision profile, per-site choices) are stored in your browser’s local extension storage. Your colour-vision profile is never sent to us or to the websites you visit.
- In dark mode, where words sit on top of a picture the page does not let any extension read (a WebGL animation, protected video), the extension asks the browser for one screenshot of the tab you are looking at and reads a few dozen pixels around those words to check they are legible. This dark-mode sample screenshot is used on your device within a moment and discarded. Only a handful of colour values leave the browser’s background process on their way to the page you are viewing. This happens only while that tab is in front, a few times per page at most.
- Accessibility audits (Audit mode, Pro Tester) run in your browser. An audit reads the page you chose, applies zoom, text spacing and colour filters to it for a moment, takes screenshots of that tab and puts the page back. The full results, elements, screenshots and checklist notes stay in your browser unless you choose to upload a report. If you enable the account audit-list setting, which is off by default, the extension also sends the limited summary described below.
- The extension contains no analytics or advertising code and does not send general browsing-history telemetry, page content or your settings. Some specific service requests and optional account records are described below.
- To fetch cross-origin stylesheets and images that a page itself references, the extension requests those same files from their own servers, without cookies.
- Your free-trial record (start date, length and a signed confirmation from us) is kept in your browser in up to three places (the extension’s storage, Chrome Sync if you use it, which is synced by Google, and the extension’s IndexedDB) so that reinstalling, or clearing one of them, does not silently restart the trial.
What we process when your free trial starts
The trial needs no account and no card. To prevent repeated trial registrations, the extension contacts our licence service in the background when the trial starts. That registration request includes:
- a random install ID (not derived from your device or identity), a small proof of work (a few seconds of computation at most, usually instant), and the date it believes the trial started;
- after a reinstall, the signed trial confirmation we previously gave your browser, so that your original start date carries over.
Like any web request it reaches us from your IP address. We do not store the address itself. We store keyed one-way hashes of your install ID and your network prefix (the first three parts of an IPv4 address, or the first 56 bits of an IPv6 address, shared by many households); the network-prefix hash is re-keyed every calendar month. These hashes help detect unusually repeated trial registrations and are deleted after 180 days. To stop a trial restarting after an extension reinstall, we also keep, for up to 400 days, a keyed hash of your network prefix combined with a broad operating-system class (Windows, macOS, Linux, ChromeOS or Android, read from the request header your browser sends anyway), together with when the last trial there began and ended. That record contains no install ID or address. If you sign in, we also keep your trial’s start date and length with your account until you delete it. Trial registration does not include URLs, page content, settings, colour-vision profile or cookies. The trial lasts six months and does not collect payment details.
Audit reports and accounts
- Counting and sealing reports: when a full audit starts, the extension sends our service its random install ID (and your licence token if you have Pro Tester) to check the report allowance. When it ends, it sends a report ID and SHA-256 fingerprint so the service can seal it. These requests do not include the page address, content, findings or screenshots. We retain the allowance record, keyed identifiers and fingerprint for up to 400 days.
- Account audit list (optional, off by default): if you are signed in and enable Show every audit in my account, the extension sends the audited host name, date, WCAG level, failure and review counts, and whether the report is sealed. It does not include the rest of the page address, page title, page content, elements or screenshots. Turning the setting off stops future entries; entries already sent remain until you delete your account or the related stored report.
- Account activity (for signed-in accounts): the account records events such as sign-ins, audit/report actions, project and issue changes, and plan changes. An event can include its time, type, a short label (which can contain a site host, project name or issue title), object IDs and limited counts or status values. It does not include page content, screenshots, issue descriptions or comments. The account keeps up to the 2,000 newest events and deletes them with the account.
- Account workspace (when you use the app): information you enter or import can include your profile name and role, organization name and details, project names, website addresses, journeys and descriptions, checklist answers and notes, issue titles and descriptions, page locations and element details, comments, and screenshots you attach. It is stored in your account until you delete the relevant items or account.
- Accounts (optional): if you sign in to the website or extension with an email code, the service stores a random account ID, a one-way keyed hash of your email address (not the address itself), last-use time and hashes of your session secrets. The extension keeps the address locally to show which account is signed in. We send the address you enter to our email provider to deliver the code.
- Full report uploads (only when you choose): when you save a report to your account, choose Upload in the app, or enable automatic upload in the extension, the report is uploaded and stored with its findings, page address, screenshots and checks until you delete it or the account. Automatic upload is off by default. Deleting an account erases its reports and share links at once.
- Share links (only when you create one): anyone holding the link can read that report, without signing in, until it expires (7 days to 1 year) or you switch it off. The page does not reveal who shared it, is not indexed by search engines and sets no cookies.
- Checking a report: the checker on our website computes a fingerprint of the file in your browser and sends only that and the report ID.
Website analytics
On eligible informational pages of this website, Microsoft Clarity may collect page interactions and session replay data only after you choose Allow analytics. The Clarity script is not loaded before consent. It is disabled on the homepage, which accepts website addresses for previews, and on the checkout return page, which can contain a temporary session token. Advertising storage is always denied. You can change your choice through Cookie settings in the footer. Microsoft processes this data under its own privacy terms; see Microsoft’s Privacy Statement.
This website analytics does not run inside the extension. The extension has no general usage analytics. The account activity and optional audit-list records described above are limited account features, not browsing-history tracking. Product-level trends can be reviewed through aggregate statistics provided by the Chrome Web Store.
Website image previews
If a website blocks the live preview on our site, you can choose Show image preview. That sends the address you entered to our Cloudflare Browser Run service, which loads the public page and returns a temporary WebP image with an approximate dark treatment. LumensOS does not save the address or image. The image stays in your browser’s memory and is cleared when you preview another address or close the page. This is a visual approximation; it does not run the LumensOS extension or confirm how the extension will render that site.
What we process if you subscribe
- Payment: handled by Stripe. We never see your card number. Stripe shares with us your customer and subscription identifiers, plan, status, renewal date and the email you entered at checkout.
- Licence record: a random licence ID, the Stripe identifiers, plan, status, renewal date, and a one-way keyed hash of your email address (we cannot read your address back from it).
- Install ID: the extension generates a random ID so a licence can be tied to your browser. It is not derived from your device or identity. At most three installs are kept per licence.
- Restore emails: when you ask to restore Pro, you type your email; we use it once to check for a subscription and to send a one-time code through our email provider, then discard it.
Other extension requests support account sign-in, report allowance checks and sealing, optional audit-list sync, report uploads you choose, licence restore and renewal, and downloading the site-fix library (signed data files that guide LumensOS on particular websites). These requests use the random install ID and, where applicable, a licence token or signed trial confirmation. The site-fix and licence requests do not include the sites you visit or your settings. Report content is sent only when you choose to save or upload a report, or enable automatic upload. Free audits still use allowance and sealing requests; paid plans add licence checks.
Who else is involved
- Stripe (payments, invoices, billing portal), subject to Stripe’s privacy policy.
- Cloudflare (hosting and Browser Run image rendering) processes request metadata to deliver and protect the service. It receives a website address only when you choose to make an image preview.
- Our email provider delivers restore and sign-in codes.
Retention and your rights
We keep licence records while your subscription is active and as long afterwards as needed for refunds, disputes and legal or tax obligations. You can ask us at any time to see or delete what we hold by writing to sandun@stringsos.com. Depending on where you live you may have further rights (access, correction, erasure, objection); we honour them regardless of location.
Children
LumensOS is not directed at children under 13 and we do not knowingly collect their data.
Changes
If this policy changes in a way that matters, we will update the date above and, for material changes, tell you inside the extension.