Safari on the Mac logs me out of Merus every time I open a PDF

Safari has its own PDF reader, but it's trying to use a different version installed on the Mac.  In order to prevent this, you can move the plugin named "AdobePDFViewer.plugin" out of the Internet Plug-ins folder.  Once you've done this, Safari should use its native PDF reader, thus solving the problem.

To find Adobe.PDFViewer.plugin, open your hard drive (it may be on your desktop; if not, use the finder or the spotlight tool in the upper-right hand corner of the screen).  In your hard drive you'll find the Library folder:




In the library folder you'll find a folder labeled Internet Plug-ins. 




In that folder is an item named "AdobePDFViewer.plugin."




Move this item out of the Internet Plug-ins folder.  When you have done this, restart Safari.  You should now be able to view PDFs without any problem.