There is different forms of REGEX used in different places.
The Add books template is (almost) nothing like the REGEX used in the Metadata S&R Which is nothing like the Save/Send to template
BTW Calibre stores series_index as Real numbers internally, not as a string.
This is the one I suggested
https://www.mobileread.com/forums/sho...ighlight=REGEX
It is useful in S&R (and the Sigil EPUB editor)
Neat cat (A meese, the best kind

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