Is ENstaCRYPTION Secure | Let Media Freedom Ring

The Short Answer Is Yes And No
YES - Associates Receive Access To The Fully Harden Secure Use That Was Created For Crypto Via Email Implementation.
Excuse The Language But Our Outside Security Expert Gave This Analysis - "Together, these layers give you defense‑in‑depth: even if one layer were weakened, the others still protect the message. That’s why ENstaCRYPT can be considered a high‑ass‑security way to exchange confidential text.
ENstaCRYPTION Developer Has Contracted With A Bank To Apply Crypto Via Mail Implementation

NO - The Code Applied Here Is Very Good For Normal Secure Messaging But Is Vulnerable To The Following Attacks

XSS or malicious extensions

If an attacker can inject JavaScript into the page (e.g., via a vulnerable third‑party widget, a compromised host, or a malicious browser extension), they could read the master‑code hash, capture the password you type, or replace the crypto functions.

Local‑storage exposure

The Argon2 hash + salt are stored in localStorage. If an attacker gains access to the user’s device (physical access, malware, or a compromised browser profile) they can read those values and launch an offline brute‑force attack.

Kyber stub is not a real post‑quantum KEM

The stub adds no real post‑quantum security; it’s essentially a deterministic SHA‑256 operation.

Password reuse

Users might reuse the same encryption password across many messages. If that password ever leaks, all ciphertexts encrypted with it become vulnerable.

Browser compatibility

Very old browsers may lack crypto.subtle or Argon2 support, forcing the fallback to PBKDF2 (still decent but weaker).