Separated origins
The informational site lives at watermarkpdfonline.com. The editor lives at app.watermarkpdfonline.com. Browser storage is origin-scoped, so code on the public site cannot read signatures or stamps saved by the editor.
No document backend
The editor is a static build. There are no upload endpoints, API routes, databases, server functions, analytics SDKs, or server-side PDF fallbacks.
Network-denying policy
The editor sends a Content Security Policy with connect-src 'none', bundles its PDF worker and font, and blocks framing. Once its static assets have loaded, document work continues without a network connection.
Limits
A website cannot protect a device that is already compromised. Browser extensions, screen-capture tools, malware, or another person with access to the computer may still see local content. Always use a trusted device and an up-to-date browser.
Responsible disclosure
A dedicated security contact will be published before broad launch. Until then, do not upload sensitive samples when reporting a problem.