'Format Value' behavior with Unmatched $regexp

Support
9

When I wrote ...

This works for me ...
TITLE MATCHES "^.[\W-.\s]Op(?:us)?[-.\s]?(\d+).*?$"

... then it works in Mp3tag.
I checked it thrice using your examples.

See there for other inspiration ...
/t/16152/1

DD.20141130.1026.CET