A PDF, a Word file, a screenshot, a photo of a whiteboard or a scanned page can be the source of a video. Pages with text are read directly; pages that are images are looked at and transcribed. If a page has no words in it at all, we say so rather than inventing them.
Before this, uploading either of them failed on the live site in every version that had shipped, and the error named the very format you had just given us.
The explain.ink mark on a video is quieter, and the tabs on a finished video open instantly.
Choose how your video opens and how it ends, pick the style, the narrator and the frame each in its own window, and have your own script checked before anything is made.
A finished video opens in four tabs, and one of them writes the post that goes with it, for the network you pick, from what your video says.
Everything that changed, newest first.