UnstableChanges

Summary

  1. Backport #5643 into Pharo8, fixes #6418 (details)
Commit 52aed88f6923d0d442dd762751dfdcc1c6d9910e by marcus.denker
Backport #5643 into Pharo8, fixes #6418
The file was modifiedsrc/Kernel/Class.class.st (diff)
The file was modifiedsrc/Kernel/UndefinedObject.class.st (diff)
The file was modifiedsrc/Kernel-Tests-Extended/ClassTest.class.st (diff)