Colorless text when writing a new text in a PDF

In the meantime....

You could try an old pre-press trick we use to "refry" problematic PDFs:

Export your PDF as an EPS file (making sure in Settings under fonts to select Embedded and Referenced fonts, and, Under Color Management, select Same as Source).

Once that is done, open that resulting EPS in Acrobat. This will invoke Distiller (it will warn you about trust, click OK) and will regenerate the PDF.

It should be editable after that.

Yes. I am seeing the same thing. I was able to recreate the issue.

Oddly, the entire document will not allow editing, even to the existing text on the page. There doesn't seem to be any Security/editing restrictions on the file, so this is weird.

Even more odd, I can copy and paste any "invisible text" created in your document into another PDF and it shows properly. although the reverse is not true.. i.e. added text on my other PDF will not paste into your document.

Also: I attempted to place the PDF into an InDesign document and it fails to import.

It WILL open in Illustrator (although wih the expected garbled encoding).

Stay tuned.

Obviously, I have already tried selecting my text and choosing a colour that is different from white. But this does not solve the problem, and the text still does not show.