New answers tagged osx
Preview is simply a terrible PDF viewer. It has many rendering issues with PDFs. Preview is designed by Apple to view PDFs for average home end-users. It is not designed to be a professional PDF viewer. Apple simply appears to not be concerned with many rendering issues in Preview where PDFs are concerned. What you are describing I'd actually call one of ...
There is a Sketch vector UI kit http://yosemiteui.com You can export it to PDF and import in Illustrator.
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