The visual reads pdfs from the Power BI data model which requires the documents to be converted into base64 encoded strings before imported into the data model.
The visual is restricted to display one pdf at a time and will display a warning otherwise.
With one document selected the Pdf Viewer displays pdf documents with controls that enables the user to switch pages and zoom in and out. On the format pane there are also possibilities to show/hide header controls and overflow scrolling.
It is most suitable to use with small document since columns in tabular models can contain maximum ca 30.000 characters.
The workaround for files that require more characters is to split the strings into multiple columns on import and concatenate them back to their original form in a computed column (see example pbix file).
Sample pbix contains two examples: