equals

Content equality, including codecExtradata.

A data class compares a ByteArray by REFERENCE, so two descriptions of the same stream from two probes of the same file compared unequal purely because each held its own copy of the same bytes. Anything keyed on a stream, cached by one, or checking that a stream belongs to a source inherited that instability.

The array itself is still the caller's to leave alone: it is exposed directly rather than copied on every read, and mutating it after construction changes what this compares. Making the bytes structurally immutable is an API change and belongs with the immutable-descriptor work, not here.