rfc2047-encoded-word-regexp

rfc2047-encoded-word-regexp is a variable defined in `rfc2047.el'.
Its value is

"=\\?\\([^][- ()<>@,;:*\\\"/?.=]+\\)\\(?:\\*[^?]+\\)?\\?\\(B\\?[+/0-9A-Za-z]*=*\\|Q\\?[ ->@-~]*\\)\\?="

• This variable may be risky if used as a file-local variable.

Documentation:
Regexp that matches encoded word.