This hack fixes a reset bug present in the European Classic Series release of Mario Bros., where the game would not start in some conditions. The region flag in the header has been fixed as well, so this is an ideal base for future hacks.
Database match: Mario Bros. (Europe) (PAL-MC-0, Classic Series)
Database: No-Intro: Nintendo Entertainment System (v. 20210216-231042)
File SHA-1: 279EFE66203114FC8A5335CB2710FF8F1CD6BBF5
File CRC32: 5F1DFF9C
ROM SHA-1: DBD1BF833A9D89A9AC41CCCED0FB508074A489D1
ROM CRC32: A1C0DA00