When you start the "Create new" workflow, you can see a history of uploaded assets, ready for reuse!
This goes for URL's, PDF's, audio, and video files.
History is limited to 12 items/one week, depending on how much source content users upload. The history is user-specific, so you’ll only see items you’ve uploaded.
Assets from other projects will be copied into the new project, which means you won’t be able to reuse the original files (e.g., with any edits or corrections).