A few of the documents you can obtain through REsearch will be in a PDF file format.
The method of displaying these files are largely up to your browser. Your browser may be set to show the contents within it’s own window or it may be set to download the file into your downloads folder and open it with a PDF viewer program.
Here are guides on choosing how a PDF will be displayed;
Adobe acrobat – troubleshooting (links out to adobe.com site)
You can also find a “display in browser” selection within Acrobat/Reader that may be helpful.
*Changing the PDF settings on your browser will affect all PDF downloads from all websites.