Z:gnu-www-ja-netscape-npl-old--479c83-This conflict occurs because t/en

This conflict occurs because the GPL is serious about copyleft: it was designed to ensure that all changes and extensions to a free program must be free. So it does not leave a loophole for making changes proprietary by putting them into a separate file. To close this loophole, the GPL does not allow linking the copylefted program with code that has other restrictions or conditions&mdash;such as the NPL.