When using copy/paste to bring the search results into the Navigation Area, the actual files are downloaded from UniProt.
To copy/paste files into the Navigation Area:
select one or more of the search results | Ctrl + C ( + C on Mac) | select location or folder in the Navigation Area | Ctrl + V
Note! Search results are downloaded before they are saved. Downloading and saving several files may take some time. However, since the process runs in the background (displayed in the Toolbox under the Processes tab) it is possible to continue other tasks in the program. Like the search process, the download process can be stopped, paused, and resumed.