A popular site (http://18.104.22.168/~khchung/cgi-bin/plutil.cgi) that converts binary .plist file to ASCII/Text XML .plist file is down for quite sometime. I decided to mirror the site, but instead of Perl, I am using PHP to do it. Similar to the site, the processing is done by http://homer.informatics.indiana.edu/cgi-bin/plutil/plutil.cgi/ .
Here is the link: https://lesterchan.net/plutil/ 
Just in case you are wondering, .plist is used by jailbroken iPhone to modify settings such as font face, font size, font colors, etc. If the file is in binary, you can’t modify it and hence this converter converts the binary content within the file to ASCII/Text and this will allow you to modify it.