Big JSON Viewer is an open-source project. The fastest way to reach us is on GitHub.
Open an issue at github.com/bigjsonviewer/bigjsonviewer/issues. Please include your browser, the approximate file size, and steps to reproduce.
If you believe you have found a security issue, open a GitHub issue marked security, or use GitHub's private vulnerability reporting on the repository. Please do not include exploit details in a public issue.
Start with the Privacy Policy — it covers what data the app touches (short version: your JSON never leaves your browser). Anything unanswered, ask via GitHub.