Incorrect handling of signature's Unicode properties Reason and Location
Okular:
Same document in Acrobat Reader:
See PDF spec, 3.8.1:
For text strings encoded in Unicode, the first two bytes must be 254 followed by 255, representing the Unicode byte order marker, U+FEFF. The remainder of the string consists of Unicode character codes, according to the UTF-16 encoding specified in the Unicode standard, version 2.0.