While working on a different project I realized I could create something fun: a font that shows every letter as a circle. That way, if you select some text and set it to this Privacy font, the text will become illegible to anyone glancing at your screen.

If you want to be able to read the text again, select it again, and switch it back to any normal font.
This can be useful for people working in public facing goverment agencies, such as the police or local councils, where they may have sensitive data on their computer monitors, but also want to briefly show those displays to people. This way they can quickly and temporarily hide a part of a text, while keeping other parts legible.
I was surprised that I couldn’t find an existing font that already did this, so I decided to make it:

I could have done a more optimal job, but for a prototype it works well.
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This font is made available under an Open Font License, which means you can use it however you please, and you can share it, but you cannot sell it.