wtf is obsidian-one-file?

One File is a plugin for the note-taking app Obsidian that lets someone edit any markdown file already on their computer directly from inside their Obsidian vault, without moving or copying that file into the vault first. Instead of duplicating the file, the plugin creates a link to the original file on disk, so any edit made in Obsidian is actually saved back to the real file in its original location. This is desktop-only software for Mac, Windows, and Linux, and it will not install or run on the mobile version of Obsidian. Once installed, users can open an existing markdown file through a file picker or by typing its path directly, and the plugin will create a new file at that path if one does not exist yet. There is also a focus mode command that hides the sidebars, tabs, and status bar for distraction-free writing, and a cleanup command that removes links pointing to files that were deleted or moved. When a file is opened, the plugin creates a link inside a visible folder in the vault that mirrors the file's original location on disk, so users can see exactly which files the plugin is tracking. The README is clear about some limitations. Because these links are filesystem symlinks, cloud sync services like iCloud, Dropbox, or Obsidian Sync generally do not carry them between devices, so the plugin is meant for editing files on the same computer where they live. Files in protected folders on macOS, like Documents, need Obsidian to be granted Full Disk Access first. Since the link folder is visible in the vault, linked files also show up in Obsidian's search and graph view unless manually excluded. The plugin is built by an independent developer, Anand Ramanathan, who also links to a few of his other projects and an optional donation page.