Nemo remove Contains ext and the CollectionUtilities class
Nemo remove Contains ext and the CollectionUtilities class

original commit: vintage-software/vstack@5b7e520d9d0c0e3eae5d389fb37f617fb81a1528

split from cb2b3ca9fd1a2384b59c0e7805daf5447e95c069

vintage-software/vstack