Security model
LeanPaste observes Windows clipboard-change notifications and processes image clipboard content only. It does not read clipboard text, contact a network, launch other processes, install a service, request elevation, load remote code, or retain image history.
Safe failure
LeanPaste replaces the clipboard image only after optimization succeeds and exceeds the configured minimum-savings threshold. If decoding, encoding, clipboard access, or settings work fails, the original clipboard remains unchanged.
Defensive image limits
The app rejects images above 32,768 pixels on either edge or 50 million total pixels. It scans alpha data and preserves any image containing a non-opaque pixel rather than risking damage to meaningful transparency.
Local storage
Images are never written to disk. The only persistent file is a bounded plain-text preferences file in the user's local application-data folder. The temporary Restore image exists in process memory and is cleared when restored, replaced, or the app exits.
Startup and privileges
LeanPaste runs as the ordinary signed-in user and requests no administrator rights or UIAccess. Optional startup uses the packaged Windows startup-task mechanism and remains visible and reversible in Windows settings.
Release gates
Internal development packages are unsigned and are never public downloads. The first public release is planned for Microsoft Store only. The exact submitted package must complete current Windows App Certification Kit, Microsoft Defender, clean-install, update, uninstall, compatibility, and private Store-flight checks before public release.
Report a vulnerability
Please email support@everfixedstudios.com with the subject “LeanPaste security report,” plus the LeanPaste version, Windows version, steps to reproduce, and the result you observed. Do not include private clipboard images unless we specifically request a sanitized example.
Related information
See the privacy policy for data-handling details or the support page for product help.