If a class has a class document or data sheet, it will be indicated in the tree and selection display with a separate icon.
Also in the context menu, the function Class Document / Data Sheet is available. A click on the icon will show the linked original file, respectively the data sheet.
If a class document and a data sheet are available, the object to show must be selected in a popup windows.
How to deposit data sheets is described in Customizing Manual ESB | ProEasyBrowse | Integration & Enhancement
As data sheets are filed physically on a data carrier, independently from SAP, the locally defined viewer will be used to show the documents.
A class document will be opened with SAP DMS and the viewer set in SAP DMS customizing will be used.