A merging obfuscator can leave a module referencing two versions of the same
assembly. Loading both split every type they declare into two definitions that
compare unequal, so a signature naming such a type through one reference stopped
matching a base method naming it through the other, and a genuine override was
printed as virtual. ac0ef8a11 (#3253) dropped the lower-version duplicates, but
nothing covered that, and neither of the existing fixture kinds can carry the
three assemblies the situation needs.
Assisted-by: Claude:claude-opus-5[1m]:Claude Code