[lukasschwab]

Interesting. Did some quick poking around.

Looks like the system adds a number of non-printing unicode characters into the string. In this thread title, for example, the textmark is stored in the phrase "mess⁡a⁠g⁣e⁣ ⁣h⁢a⁣s⁣ ⁢a⁣ ⁢h⁠i⁠d⁣d⁢e⁢n⁢ ⁠m⁠e⁢s⁣s⁢a⁠g⁣e⁣ ⁠i⁠n⁡side." (Thanks, textdiff!)

Specifically, it adds non-printing unicode characters repeatedly. I'd guess these form a unique series, which is mapped to a record in the textmark database.

If I wanted to automatically remove the textmark from a text, in order to steal your content, I would write a script to automatically remove any non-printing unicode characters that appear in it. This StackOverflow answer includes a script achieving precisely that task: https://stackoverflow.com/a/11598864/6226586

[ozgrozer]

I was thinking the same things like you. Looks like they don't event hide the actual message. They basically hide some sort of ID that points a row in the database. After some research I've made a web-app which can hide any message into any text.

If you wanna look it's on G⁡⁠⁢⁠⁠⁢⁠⁣⁠itHub. Here are the links.

Demo: https://ozgrozer.github.io/titus/

Source: https://github.com/ozgrozer/titus/

[lukasschwab]

Also, this reminds me of a Clara Labs (YC S14) project to hide unique IDs in unicode text: https://blog.claralabs.com/invisible-ink-a-simple-but-faulty...