Case-insensitive search folded the query and the page with
str::to_lowercase, which follows no locale: U+0130 (İ) becomes "i" plus a
combining dot above (two characters) and U+0131 (ı) has no case pair. So
"istanbul" never found "İSTANBUL", and "ırmak"/"kış" never found
"IRMAK"/"KIŞ" (or the reverse). The same PageText::find serves Find,
Search & Redact (phrases and word lists) and the automation text search,
so Turkish words could also be left unredacted.
Fold I, i, İ and ı to "i" and every other character with its own
lowercase, one character for one character. Case-sensitive search is
unchanged.
snipeTR
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