Conversion:
* Added support for Emoji 18.0 and updated emoji data to CLDR 49 [1638d1d, 59fc17c]
* Suggested the corresponding day of the week (e.g. " (水)") as a prediction immediately after committing a date expression (e.g. "9月16日", "2026/09/16") [6d51df3]
* Allowed conversion candidates across segment boundaries when typing alphabet words consecutively (e.g. user dictionary words with alphabet readings) (#1598) [1f3c171]
* Applied user conversion history consistently regardless of full-width or half-width character forms [93dcdbd]
* Prevented common words and compound expressions from unintentionally converting to all-Katakana (e.g. "ちょいのり" -> "ちょい乗り", "こてでかーるする" -> "コテでカールする") [efd6431]
* Added new words and OOV words reported by users [c152385, 8be758d]
* Improved conversion accuracy for sentences with omitted particles (e.g. "さかなくう" -> "魚食う") [c08fbbd]
* Supported selecting long multi-segment candidates at once in prediction and conversion (dates, calculations, numbers, etc.) [3d4d388, 18b366f, 69d53ca, 423687d, 802b34c, a179b7e, b6667bd, 116ec4a, 2320800]
* Suggested matching closing bracket immediately after committing an opening bracket (e.g. "（" -> "）") [ed4eec6]
* Prioritized frequently used counter suffixes (e.g. "個", "本") when following numbers based on input history [6621478]
* Remembered full-width / half-width preferences from mixed-script words and real-time conversion [921b8cc]
* Improved character form conversion and alternative suggestions for mixed-script words (e.g. "Tシャツ" <-> "Ｔシャツ", "3時" <-> "３時") and formatted numbers ("3.14", "1,000") [149f38c]
* Prevented character form learning in incognito mode and avoided overwriting preferences from unselected candidates [5750c5f]
* Prevented unintended full-width number preference when typing compound words (e.g. "2日") or Kanji numbers [ea4b46c, 9dbd38d]
* Suppressed unwanted symbol candidates and large user dictionaries from overriding common conversions [3f235b4, 4d56b45, 698e1db]
* Desktop: Supported learning preferred number styles (half-width, full-width, Kanji), matching mobile behavior [d724768]
* Desktop: Enabled character form preference learning when committing suggestions and predictions [5750c5f]
* Mobile: Kept short word suggestions visible in the suggestion strip even when longer history matches exist [839404c]
* Mobile: Displayed numbers in user's preferred character form (half-width / full-width) in suggestion lists [22ff5f1]
* Mobile: Enabled automatic typing and homonym corrections during conversion [b2e087f]
Features:
* Unified user conversion history and prediction clearing in ConfigDialog [14882c3]
* Linux: Supported typing symbols and characters with AltGr (Mod5) and Level 5 Shift (Mod3) modifier keys in IBus (e.g. Bone and Neo2 keyboard layouts) (#1590) [dcb6af7]
* Linux: Prevented unintended input interference when using shortcuts with Super, Hyper, or Meta keys in IBus (#853) (#1567) [15c2537]
* macOS: Suppressed redundant input source confirmation dialogs during automated installations and when already enabled [18b49c5]
* macOS: Restored license agreement prompt for the dev channel package on modern macOS versions [a24a993]
* macOS: Improved input source registration and installer reliability on modern macOS versions [1338d76, e8c987a, 01de516]
* Qt: Added initial dark-theme support for mozc_renderer with Qt 6.5+ (#1582) [2dd33cb]
* Qt: Added vertical indicator (#1565) [bd0845a]
* Qt: Supported footer label in candidate window (#1580) [a069a88]
* Qt: Refined styling, colors, and candidate view layouts (#1549, #1551, #1586) [0651fbc, ab0c249, 9fbd649, c7538e6]
* Windows: Reduced memory footprint of the Mozc server on Windows 10 (2004+) and Windows 11 (#1541, #1572) [3dec806, fa755aa]
* Windows: Clarified installation failure message on Windows ARM64 (#1585) [5fb8e95]
Bug fix:
* Fixed an issue where stale prediction candidates from prior contexts could unexpectedly appear as the top suggestion [4bdaa00]
* Fixed a race condition where clearing conversion history could be undone by background storage tasks [ee423e2]
* Fixed typos in configurations documentation (#1602) [c61e99d]
* Fixed the loop condition in SortAndVerifyUnique (#1538) [d73e864]
* Fixed bounds check in CandidateList::MoveToPageIndex (#1544) [7f1973b]
* Fixed potential infinite loop in DictionaryTool (#1545) [e7ab408]
* Fixed invalid transition cost scaling in Connector 1-byte format (#1589) [3e6ddc0]
* Fixed converter_main failing to persist Segments and Composer state across commands [63adc55]
* Fixed crash caused by out-of-bounds access when incognito prediction produces no candidates (#1563) [9ff04cf]
* Windows: Retried atomic file saving on sharing violations to prevent save failures in user dictionaries and settings (#1597) [54af324]
Code:
* Reduced heap memory usage of connection tables in Mozc server by 804 KiB (-68.8%) (#1596) [0fd2070]
* Decoupled core dictionary engine from UserDictionaryStorage and moved user dictionary storage/importer to client/user_dictionary [694d646]
* Removed obsolete CLEAR_UNUSED_USER_PREDICTION command and ClearUnusedHistory APIs [1cd3840]
* Android: Removed unused touch event statistics generation target and data [9eaf622]
* Refactored prediction decoders by extracting HandwritingDecoder, ZeroQueryDecoder, EnglishDecoder, and DictionaryDecoder, and merging aggregator into DictionaryPredictor [885b51f, b30717c, fba4bd2, 57dea2c, 54cbccf, 0949067]
* Modernized UserDictionary storage and direct database generation without obsolete IPC protocols [2fc02b0, 7262b53, ff99671, f91f569, 1ab7fc8, 80eadd0, c60e7d4]
* Migrated CharacterFormManager storage from cform.db into UserHistoryStorage [b7277bb]
* Implemented PosIdMap and dynamic POS pattern matcher PosPatternMatcher [cb11f9c, b5ac73a, 88da9b4]
* Supported <NWP>-prefixed entries in SuggestionFilter / ResultFilter [d3f6b7c]
* Optimized strings::CharsLen with std::popcount (#1568) [144bdc6]
* Optimized bit selection with std::countr_zero (#1569) [a1c13ed]
* Optimized SimpleSuccinctBitVectorIndex::Rank1 with 64-bit operations [13fd62b]
* Optimized CachingConnector with tag-based caching and if constexpr [d918f30]
* Supported move semantics and pass-by-value across Token and decoders [13c9898, 2bd30ce, 6ea1849, 7ebdfa8, 6231a57]
* Introduced converter_util library for Segments and prediction::Result conversions [8f9100b, c3f3c14]
* Used std::filesystem::last_write_time in FileUtil::GetModificationTime [e9fb7c4]
* macOS: Removed obsolete InstallerPane plugins and packaging targets [6c1e1d2]
Build:
* Added micro-benchmarks for BitVectorBasedArray (#1592) [5076709]
* Supported regular expressions in "Conversion Match" and "Conversion Not Match" evaluation rules [d482471]
* Switched GitHub Actions runner to Ubuntu 26.04 (#1578) [5375360]
* Pinned GitHub Actions dependencies to commit hashes (#1579) [7eff5b3]
* Enabled Linux CI workflow on pull requests [73b1a59]
* Uploaded test failure logs in GitHub Actions (#1527) [7c1e06d]
* Updated GitHub Actions macOS runner (#1536) [7979e66]
* Supported Windows 11 Arm64 CI runner and resolved toolchain issues (#1533, #1534, #1535, #1537) [08aac93, 8f2cf19, 9d2a86d, 379723a]
* Integrated Google Benchmark support and added micro-benchmarks (#1555, #1556, #1575, #1588) [416af15, 591720e, 7167579, 14e69ba, 41879bc, b9c3fcb, dc7ceb6]
* Added regression and evaluation test cases for sentence-ending particles and particle omission [1ad071c, dc16724, ff395ce]
* Supported host architecture build in build_qt.py (#1532) [96b314d]
* Embedded Win32 manifest into tests and build tools (#1529) [9bc6919]
* Fixed incomplete-type error in candidate_list.h under C++23 (#1573) [fd7eff0]
* Qt: Fixed build error with Qt 6.12 uic by removing leading "::" from custom widget in dictionary_tool.ui (#1594) [29c082a]
