1) Ctr + F = Search 2) Search for 'ñ' into a file ( 'Spanish Document' in Options / Language Settings / Language of / Locale Setting ) 3) It returns 'n' characters too.
Confirmed. But by design. IIUC the search engine for the Find toolbar uses the ICU lib transformation to make search insensitive to diacritic markings (e.g. tilde, acute, caron, etc.) meaning the Find toolbar search will return both 'ene' and 'eñe' of Spanish scripts as they are treated as the same base for Unicode search. This was a design decision to keep the <Ctrl>+F find bar lightweight, and applies equally to all scripts and locales. The more robust 'Find & Replace' dialog provides the 'Diacritic-sensitive' checkbox. It is enabled by default for all locales, and the search with ICU libs does not combine the codepoints. Search for specific glyphs (U+00D1 LATIN CAPITAL LETTER N WITH TILDE), or (U+00F1 LATIN SMALL LETTER N WITH TILDE) succeeds.
Quick find bar is diacritic sensitive for me (only one ñ) and the search dialog (ctrl+H) allow both. Agree with Stuart on WFM. Feel free to reopen if you think there is need to tweak the implementation (your use case is missing).