Last updated: April 4, 2026 · Filtr Nieruchomosci · [email protected]
Filtr Nieruchomosci is a Chrome extension that runs entirely in your browser. It is designed to work on otodom.pl and olx.pl (including www variants). The extension does not send your data to developer-owned servers and does not sell personal data.
The extension stores data only locally in your browser using Chrome extension storage APIs.
chrome.storage.local: hidden listings blacklist — listing identifiers you chose to hide, plus metadata used for the popup (city key/label derived from the listing or search context, and whether the entry was saved from Otodom or OLX).
chrome.storage.sync: UI language preference for the extension popup (Polish/English). This may sync across your signed-in Chrome devices via Chrome’s built-in sync. The developer does not receive this data.
The developer has no access to stored data.
To provide hiding, optional visual highlights (for example non-private/agency-related signals), and the popup summary, the extension processes website content on otodom.pl and olx.pl in your browser, such as: listing cards, titles, prices, links, and other DOM elements needed to locate offers and render controls; public offer-page HTML patterns used only to infer seller type signals for display in your browser (no uploading of page content to developer servers). This processing is limited to the extension’s single purpose and happens on-device.
The extension does not phone home to developer-operated analytics/telemetry endpoints for this functionality. A background service worker may perform HTTP GET requests to public Otodom offer pages (https://www.otodom.pl/* and https://otodom.pl/*) only to fetch HTML as text when you are viewing an OLX search result that links to Otodom, so the extension can classify seller-type signals for optional on-page highlighting. Requests use credentials: omit (no cookies). Responses are not executed as remote code; they are parsed as text/HTML in the extension. OLX pages are handled via content scripts declared in the extension manifest (no additional host_permissions required for OLX in the current design).
Filtr Nieruchomosci does not: sell user data; transfer user data to data brokers or ad networks; use user data for advertising or profiling; use third-party analytics or telemetry SDKs/services.
Filtr Nieruchomosci does not collect: authentication credentials (passwords, PINs, security answers); financial/payment information; health information; precise device location (GPS).
You can remove stored data by clearing entries in the extension popup (per city or entire blacklist), and/or uninstalling the extension. Data in chrome.storage.sync follows Chrome sync retention behavior.
The extension requests: storage — to save the blacklist (chrome.storage.local) and the popup language preference (chrome.storage.sync); host access to https://www.otodom.pl/* and https://otodom.pl/* — to allow the background worker to fetch public Otodom HTML for the OLX embedded-Otodom classification flow described above. Content script access to Otodom/OLX is declared via manifest content_scripts matches.