Interesting.

The problem utilizing them ourselves, at least from my experience, is that the antis seem to obsess so much that they scan all our online places for what they are sure are secret codes, symbols and languages. They always seem to know them before we do. I cannot remember how many times I'd read or watch something in mainstream media about the "secret underworld" of pedos and some mental giblet would be warning the public of things to look for, and I'd be sitting there like "Huh. I never heard that before." I'd ask other child lovers, "Have you ever used that word or symbol as code to others like us?" Nobody else had heard of it either.

I suppose the one exception was probably the girl lover's heart-within-a heart-symbol that's still around today. Sometimes it's a pink heart within a blue heart, sometimes all pink, but that was never really intended as secret code. I seem to remember our heart symbol making it into a several page spread in the NY Times as a "secret" symbol during the height of The Great Pedo Scare anyway, roundabout summer of 2006. Great Scares have always been helped along by the NYT, after all. I thought they were selling ice cream to their readers. I wasn't far off. The only "secret" language and symbols online have been intended as humorous, as in meme forms for example. Maybe I'm just not in the secret club, which is also entirely possible.

I suppose secret greetings or phrases could work if they originated offline like in old times (30 years ago or more), but therein lies the problem in today's world, doesn't it. There is no place online where there is both anonymity and solid assurance that somebody in the group is not a disguised foil to whatever the rest are into. As a result, secret signs, phrases or handshakes would likely never work, in one person's opinion.

shibboleth?
https://www.youtube.com/shorts/H2RAtay7OX8