How do you save a marked-up PDF with Preview?
I am able to save a PDF with fields for filling in information, but some PDF files do not have such fields, in which case I use the markup tools (primarily the "Text" tool). But with the latest version of Preview (OSX 10.13.3) I have been unsuccessful. No matter what I try (Save, Export, etc.), the file is not saved with the information I've written in. The new file is just the original PDF with nothing in the blanks.
So, how do I save a PDF without losing the information I've entered?
Mac mini, macOS High Sierra (10.13.3)