629-character asynchronous function that, when run on an Actively Learn book page, generates a function to convert encrypted text to decrypted text

snippet.js

async()=>{let k="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz",l='eng',c=document.createElement("canvas"),t=c.getContext("2d");c.height=100;c.width=1500;t.fillStyle="#000";t.font=getComputedStyle(document.querySelector(".encrypted .textSection")).font;t.fillText(k.replace(/./g,"$& "),10,50);if(typeof Tesseract=="undefined")await import("https://unpkg.com/tesseract.js@2.0.0/dist/tesseract.min.js");const w=new Tesseract.createWorker();await w.load();await w.loadLanguage(l);await w.initialize(l);const m=new Map([...(await w.recognize(c)).data.text].map((l,i)=>[k[i],l]));return(e)=>[...e].map(l=>m.get(l)||l).join("")}

(There may be a better, more code-inspection-y way to do this, but that sort of defeats the point.)

Actively Learn uses a font to display some of their works that associates "encrypted" (simple A-Za-z substitution) characters with their displayable characters; this way the text displays normally, but when copied, the result is garbage.

This script draws the alphabet (A-Z, a-z) onto a canvas in the "encrypted" font then uses the Tesseract.js library to determine what those drawn characters are. Then, a Map is created to associate encrypted characters with decrypted characters, and a function is returned to convert text as such.

This should only be taken as a proof-of-concept (which is why it is an anonymous function and not a full application); do not use this program to bypass any copy protections in practice. This program was developed without any attempts to circumvent any copy protections.