vCard v3.0/v4.0 validation: stray backslashes

[respiranto]

The below only applies to v3.0 and v4.0 (i.e., not v2.1):

For properties with value type TEXT (e.g., NOTE), backslashes are only permitted as part of an escape sequence.

Currently, other (stray) backslashes are kept verbatim, and validate() does not provide an error message.

I would expect that validate() yields an error message.
Optionally, if the REPAIR flag is given, validate() might remove stray backslashes.

Example: NOTE:_\x_\:_\\_\;_\,_\n_\N_ is decoded to _\x_\:_\_;_,_<LF>_<LF>_ where <LF> is the LF (\n) character.