Show HN: JustOpenFile – Preview files locally in the browser without uploading

Hi HN,

I built JustOpenFile, a browser-based file viewer that processes files locally without uploading them to a server.

  It supports PDF, DOCX, Excel, CSV, JSON, Markdown, EPUB, ZIP, SQLite, images,
  audio, video, fonts, and 3D formats such as STL, GLB, and OBJ. ZIP archives
  can also preview supported files inside them.

  The project was motivated by a simple problem: opening an unfamiliar file
  often requires installing an application or uploading potentially sensitive
  data to an online service.

  There is no account, installation, or upload required.

  https://justopenfile.com

  I’d appreciate feedback on file formats you would find useful and any
  compatibility or performance issues you encounter.