I'm also having trouble with the "Title-case text (ignore tags)" built-in function. I've wrapped all the UPPER case text that I want to convert to Title case in <h2> tags and am using the search parameter "(?s)<h\d>(.+?)</h\d>".
Applying "Replace-all" results in a deletion of all H tags and the intervening text. No conversion just deletion.
Editing the built-in function, this is what I see:
def replace(match, number, file_name, metadata, dictionaries, data, functions, *args, **kwargs):
return ''
Shouldn't there be more to it?