There are different ways to import, depending on which browser is used
Firefox: When you need to get the references into Mendeley, click save in this box
Make sure Mendeley is open and click the on the arrow. Drag the file down over the Mendeley icon on the taskbar. Release the file once Mendeley has opened. If the file needs to be in a special folder, remember to have that folder open before you make a drag and drop
Chrome shows downloads of the quotes in the lower left corner, from which you can drag and drop them into Mendeley
Safari - Mac
Make sure Mendeley Desktop is open
Find your downloads and select the file you just downloaded
Then pull it into Mendeley
One can also just drop it over the Mendeley icon, then Mendeley will open with the references
File names:
Web of Science: Savedrecs.bib
Ovid: ris.ris
Goggle Scholar: citation.ris
The Royal Library's library database: Primo_RIS_Export.ris
Bibliotek.dk: bibdk. [Dagsdato] _162952.ris
PubMed: pubmed_result.txt