What does the "Flatten PDF" option do?
If Flatten PDF is selected, then all layers of the design will be flattened into an image when downloaded as a PDF. The advantages of flattening the PDF when downloaded are:
1. Images and fonts can not be extracted from the final download of a flattened PDF (they can be extracted from an unflattened file).
2. Unflattened PDF files can sometimes have issues with clipping masks. Flattening the PDF will fix or avoid those issues.
For these reasons, the Flatten PDF option is selected by default when you first create your Corjl account. This can be changed in your Settings area.
Please note that flattening the PDF will not allow for vector font editing by a printing service at a later time.