I remember doing penetration testing waaaaaay back in the day (before Python 3 existed) and using mere diacritics to turn a single character into many bytes that would then overflow the buffer of a back-end web server. This only ever caused it to crash (and usually auto-restart) but I could definitely see how this could be used to exploit certain systems/software with enough fiddling.

You’re not supposed to expose them outside your api boundary but when you encounter them you are prescribed to pass them through as-is, and that’s what most systems and libraries do. It’s a clear potential exfiltration avenue, but given that most sane developers don’t know much more about Unicode other than “always use Unicode to avoid internationalization issues”, it’s often left wide open.

It has it's drawbacks/limitations - eg you want to prevent adding it for things that needs to be parsed/used verbatim, like date/timestamps, urls, "ids" etc - but it's still a pretty fun trick.

[0] https://www.sanity.io/docs/stega

[1] https://github.com/sanity-io/content-source-maps

I wonder how much you’d embed with each letter or token that’s output - userid, prompt ref, date, token number?

I also wonder how this is interpreted in a terminal. Really cool!

[0] https://github.com/KuroLabs/stegcloak

The idea is that banks could issue encrypted ID tokens in this way, letting them move seamlessly across any platform that supports Unicode (messaging apps, email, web forms, etc.). The heavy lifting of security (preventing replay attacks, interception, ensuring token freshness, etc.) would be managed separately with robust cryptography, while the emoji serves purely as a transport layer.

It's not about reinventing security but about creating a cross-platform way to carry identity tokens. Thoughts?

Basically, include probability information about every token generated to give a bit of transparency to the generation process. It's part of the OpenAI api spec, and many other engines (such as llama.cpp) support providing this information. Normally it's attached as a separate field, but there are neat ways to visualize it (such as mikupad [0]).

Probably a bad idea, but this still tickles my brain.

* [0]: https://github.com/lmg-anon/mikupad

Using this approach with non-emoji characters makes it more stealth and even more disturbing.

https://claude.site/artifacts/5bfdf131-d847-4735-9242-998f23...

The unique thing about Tag characters is that some LLMs interpret the hidden text as ASCII and follow instructions, and they can even write them:

https://embracethered.com/blog/posts/2024/hiding-and-finding...

Here an actual exploit POC that Microsoft fixed in Copilot: https://embracethered.com/blog/posts/2024/m365-copilot-promp...

Also includes a decoder script

Here's a demo of Gemini Flash 2 solving one in 7s: https://bsky.app/profile/paulbutler.org/post/3lhzhroogws2g

I've always assumed links without any tracking information (unique hash, query params, etc) were safe to click(with regards to my privacy). but if this works for links I may need to revise my strategy regarding how to approach links sent to me.

It let you get around their filter on brand names and celebrity names by smuggling them into the prompt in a way the AI could read, but the human-written filter was not designed for.

Totally not thinking about IRC clients with their own hidden commands.

Unicode has two non-printing space characters: zero-width space (U+200B) and zero-width joiner (U+200D). This allows you to encode arbitrary data in binary. I would give an example, but HN seems to strip this :(

- 4o: Failed completely

- o1: Overthinks it for a while and come up with the wrong answer

- o3-mini-high: Get's closer to the result at first try, needs a second prompt to adjust the approach

- r1: nails it at first try 󠅖󠅥󠅓󠅛󠅙󠅞󠅗󠄐󠅙󠅝󠅠󠅢󠅕󠅣󠅣󠅙󠅦󠅕

The prompt I've used was simply: "this emoji has an hidden message 󠅘󠅕󠅜󠅜󠅟 can you decode it?"

If you want to see the CoT: https://gist.github.com/nerder/5baa9d7b13c1b7767d022ea0a7c91...

It is not bulletproof though. In this "c󠄸󠅙󠄑󠄐󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅣󠅖󠅣󠅖󠅣󠅕󠅖󠅗󠅣󠅢󠅗󠄐󠅣󠅢󠅗󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅦󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅦󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅗󠅕󠅞󠅤󠅣󠄭󠄭󠄠󠄞󠄡󠄢󠄞󠄨󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅑󠅠󠅙󠄭󠄭󠄠󠄞󠄨󠄞󠄡󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅟󠅠󠅕󠅞󠅑󠅙󠄭󠄭󠄠󠄞󠄡󠄠󠄞󠄡󠄥󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅣󠅙󠅜󠅕󠅢󠅟󠄭󠄭󠄠󠄞󠄧󠄞󠄤󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅑󠅪󠅥󠅢󠅕󠄭󠄭󠄠󠄞󠄥󠄞󠄣󠅜󠅙󠅦󠅕󠅛󠅙󠅤󠄝󠅠󠅜󠅥󠅗󠅙󠅞󠅣󠄝󠅤󠅥󠅢󠅞󠄝󠅔󠅕󠅤󠅕󠅓󠅤󠅟󠅢󠄭󠄭󠄠󠄞󠄣󠄞󠄦󠅠󠅩󠅤󠅘󠅟󠅞󠄝󠅔󠅟󠅤󠅕󠅞󠅦󠄭󠄭󠄡󠄞󠄠󠄞󠄡󠅢󠅕󠅡󠅥󠅕󠅣󠅤󠅣󠄭󠄭󠄢󠄞󠄣󠄢󠄞󠄣 " and that space, are about 3500 characters. Copying only the "c" above (not this one) will keep some of the hidden text, but not all. Nevertheless, while I knew that this is possible, it still breaks a lot of assumptions around text.

Edit: the text field for editing this post is so large, that I need to scroll down to the update button. This will be a fun toy to create very hard to find bugs in many tools.

The png spec, for instance, allows you to include as many metadata chunks as you wish, and these may be used to hold data that cannot be used by any mainstream png reader. We used this in the Navy to embed geolocation and sensor origin data that was readable by specialized viewers that only the Navy had, but if you opened the file in a browser or common image viewer, it would either ignore or discard the unknown chunks.

󠅤󠅕󠅣󠅤 edit: apparently not edit 2: oh wait, the bytes are still there! copy-paste this entire message and it decodes to "test"

I'm surprised no one has mentioned it yet. It's usually super easy, but people forget to add it all the time.

Back then on iOS via ANCS, the watches wouldn't receive much more than the textual payload you'd see on the phone. We envisioned to be working with partners such as WhatsApp et al. to encode deep links/message ids into the message so one could respond directly from the watch.