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    <div class="moz-cite-prefix">Marius Spix via Unicode wrote:<br>
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    <blockquote type="cite" cite="mid:trinity-de9315c2-e08f-4c86-8120-c4cbcfb0fec2-1607945207708@3c-app-webde-bs08">
      
      
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            <div>I understand that:</div>
            <div>[:toCaseFold=s:] = [sSſ]</div>
            <div>[:toCaseFold=ς:] = [σςΣ]</div>
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            <div>But can someone explain me the following?</div>
            <div>[:toCaseFold=ı:] = [ı]</div>
            <div>[:toCaseFold=i:] = [iI]</div>
            <div>[:toCaseFold=ß:] = []</div>
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            <div>Why is it not:</div>
            <div>[:toCaseFold=ı:] = [iIı]</div>
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              <div>[:toCaseFold=i:] = [iIı]</div>
              <div>[:toCaseFold=ß:] = [ßẞ]</div>
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          <div>?
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    ß is often changed to SS in uppercase; the ẞ is a relatively new
    addition as an encoded character and is not consistently used.  So
    PREUSSEN and Preußen are casings of the same word, for example.  I
    think ẞ might have been added after ß's casefolding was already
    defined, but I'm not sure so don't quote me on that.<br>
    <br>
    "I" cannot casefold to *both* "i" and "ı", it has to casefold to one
    of them.  Not sure about "ı" not casefolding the same as "I", but I
    don't suppose there really exists any "good" locale-independent
    solution for case insensitivity of "I".<br>
    <br>
    — Har.<br>
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