Didn't find the exact information in the HTTP specification on how to validate User-Agent header value. Some sources say that it should comply to ISO-8859-1. Unfortunately the implementation in OkHttp does not cover some of the symbols in that ISO.
Solution is to copy the supported symbols from OkHttp source.
Background
Didn't find the exact information in the HTTP specification on how to validate User-Agent header value. Some sources say that it should comply to ISO-8859-1. Unfortunately the implementation in OkHttp does not cover some of the symbols in that ISO. Solution is to copy the supported symbols from OkHttp source.