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I have a content type with a field (field_title_sorting) containing the sorting order for the title. For example a title of "John Q. Smith" would have a sorting title of "smith, john q". I set up a view for this content type where I made field_title_sorting be a contextual filter with the glossary option on and a length of 1 character. That should give me list of the first letters of field_title_sorting, but instead, it is a list of the first characters from the Title of the contents. Any ideas what I could be doing wrong?