To print a proposal, first download it as a PDF from either the snapshot view or the client preview.
Once a PDF is downloaded you can open it up in Acrobat and print from there.
Download From the Pipeline
You can download a proposal straight from the pipeline page by clicking the three-dot menu to the right of the proposal. Once clicked, select "Download PDF":
Download From Snapshot View
Clicking on a proposal takes you to the snapshot, where you can click the "..." button in the top right to download a PDF copy
Download from Client Preview
From the client preview you can click the three-dot button in the bottom right and select Download PDF: