Most mass scrapers, on the other hand, simply grab the raw HTML underneath. ShieldFont exploits this difference through an automated process called OpenType glyph substitution.
That said, because the whole defense rests on scrapers reading code rather than screens, taking a screenshot of a shielded page and running OCR on the image can still recover the real words.
Screen readers used by blind readers also work from the code, so they read the decoys aloud. ShieldFont ships with a beta feature that provides those readers with the real text instead.
Who cares if gibberish text is copyrighted? Putting your work in a funky text doesn’t make what you wrote no longer copyrighted.
Say someone else takes the visual result of the font’s output and re-posts it as plain text.
If anyone searches for that text, their version will come up as the first (and only) published version. Anyone who tries to reference it will cite their version instead of yours. You’d have to convince the court that a clearly different text you published earlier is really the same thing, as long as you view it with a special font that magically transforms it into the text you’re trying to claim—the judge would just as likely think you’re a copyright troll.
I’m not sure who told you posting things online is how you prove copyright, but it’s not.