autoreg-skills-max: initial public release (restored, redacted, hardened)

skills/github-oauth-automation/references/imap-jwt-extraction.md

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+# IMAP Quoted-Printable JWT Token Extraction
+
+## Problem
+Verification emails often contain JWT tokens in URLs that are split across multiple lines due to quoted-printable encoding. The `=` at end of line is a soft break.
+
+## Example
+
+Raw email content:
+```
+token=[REDACTED]
+eyJlbWFpbCI6Im...\r\n
+3ODQ3NDM1Mzd9.qiOoGUNZZsPse1jQnZ8JHvUrb6xKX5KbPatfwvXUPGA&callbackURL=3D%2F
+```
+
+## Extraction Code
+
+```python
+import imaplib, re
+
+M = imaplib.IMAP4_SSL('imap.gmail.com')
+M.login(email, app_password)
+M.select('INBOX')
+typ, data = M.search(None, 'FROM', 'sender')
+ids = data[0].split() if data[0] else []
+typ, msg = M.fetch(ids[-1], '(RFC822)')
+raw = msg[0][1]
+
+# Find token= in raw bytes
+idx = raw.find(b'token=')
+chunk = raw[idx+6:idx+250]  # skip 'token='
+
+# Remove soft breaks (=\r\n)
+result = []
+i = 0
+while i < len(chunk):
+    if chunk[i:i+1] == b'&':
+        break
+    if i+2 < len(chunk) and chunk[i:i+3] == b'=\r\n':
+        i += 3  # skip soft break
+    elif i+1 < len(chunk) and chunk[i:i+1] == b'=' and chunk[i+1:i+2] == b'\r':
+        i += 3
+    else:
+        result.append(chr(chunk[i]))
+        i += 1
+
+token = ''.join(result)
+# Remove 3D prefix if present (= in quoted-printable)
+if token.startswith('3D'):
+    token = [REDACTED]]
+```
+
+## Important
+- Python's `repr()` truncates long strings with `...` — the actual string is complete
+- The `3D` prefix is the quoted-printable encoding of `=`
+- Always work with raw bytes, not decoded text, to avoid encoding issues
+- Use `b'...'` byte strings for searching in raw email content