The design decision
Every screen recorder that uploads to OneDrive wants a Microsoft account, a client ID, a client secret and a Graph integration. That is a lot of surface area, a lot of consent screens, and a lot that can break when a token expires.
This one does none of it. Authentication happens in the official OneDrive client, outside the app. The recorder writes a file into a folder that is already syncing, and the sync does the upload. There is nothing to authorise and nothing to revoke.
How it works
On first run it asks for the synced folder and verifies it can write and delete a temporary file there, so a misconfigured path fails immediately rather than after a recording.
You pick a screen or a window, name the recording, and record. On stop the WebM file is finalised straight into the folder, with a name cleaned for Windows, macOS and Linux and a unique fragment so nothing is ever overwritten.
Sharing hands off to OneDrive as well: the app selects the file in Explorer or Finder and lets the operating system’s own share flow decide the audience.