Do you have problems related to PDFs in EndNote on MacOS?
Primarily, these issues are being driven by the Apple PDFKit issues, which was created in Sierra with the merging of the iOS and OSX editors for PDFs. Read more further down under technical explanation.
Suggested workaround
We recommend you open the PDF in an external PDF reader when you want to read it, highlight text och make comments/annotations.
We recommend using the PDF-reader FoxitReader, although Alfasoft takes no responsibility for third-party products. This PDF-reader is small and fast and gets the job done. You can download it at the link below.
https://www.foxitsoftware.com/pdf-reader/
Technical explanation
This issue is not an EndNote specific issue, but an issue for potentially any software that is not a first-party, dedicated PDF reader.
Without a stable platform for editing PDFs, the EndNote PDF functions (and other software with similar features) will not be stable.
Until Apple addresses this issue… no amount of development on EndNote’s side is going to stabilize what is an intrinsically damaged functionality in MacOS.
We suggest all users report any PDF problems directly to Apple too but pressure for a fix, see below link.