Dear sirs: This bugs is causing errors since many years ago (at least twelve (!) [https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=139861]), and let's face it, if we don't change the point of view it will never get solved. Meanwhile, the effects of this bug will keep on damaging the works of Linux users, and our reputation.
sed can work with utf-8 correctly. What about asking help from sed developers? sed developers could even refactor the tr code so that sed code could be used, so at least this bug would not keep on causing errors to Linux users. Moreover, sed developers may find a better solution than that one. Thank you.