https://issues.dlang.org/show_bug.cgi?id=18993

          Issue ID: 18993
           Summary: toLower is broken for UTF chars
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: regression
          Priority: P1
         Component: phobos
          Assignee: nobody@puremagic.com
          Reporter: temtaime@gmail.com

static assert(`몬스터/A`.toLower.length == `몬스터/a`.toLower.length);

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