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bug-compatible adj.

[common] Said of a design or revision that has been badly compromised by a requirement to be compatible with fossils or misfeatures in other programs or (esp.) previous releases of itself. "MS-DOS 2.0 used \ as a path separator to be bug-compatible with some cretin's choice of / as an option character in 1.0."

Previousbug Up= B = Nextbug-for-bug compatible