Where a file is parsed

The desktop window is one program: every file is read and parsed in it, on your machine.

In a browser, the page decides by where the server is. When the server runs on your own machine — objectexplorer in a terminal, npx, Homebrew — the page and the server are both yours. When it runs somewhere else — objectexplorer.com, your company's server — the page keeps your own files to itself.

The file	Server on this machine	Server elsewhere
A folder or file you pick	the server: its own folder dialog, and it reads the file	the page: the browser's picker, the file kept in the page and parsed there
A file or folder dragged in	the page	the page
Cloud storage (S3, Azure, GCS, drives)	the server, with the credentials it holds	the server, with the credentials it holds
The demo, in instant mode	the server	the server

What the page holds shows in the tree under a browser:// root. It is never sent to the server, and it is gone with the page. Its pictures are made small by the browser's own decoder.

A server counts a page as on this machine only when the request comes from this machine and passed through no proxy — the same test that decides who may configure it.

Next: instant mode.