system requirements: macOS 15 and later
New Features
- Support macOS Tahoe 26.
Improvements
- Change the system requirement to macOS Sequoia 15 and later.
- Update the user interface on macOS 26 to the Liquid Glass style.
- Update the application icon to the Liquid Glass style.
- The options to highlight matching braces have been removed and they are now always highlighted.
- Apply the text find highlighting to all split editors.
- Move selected items to the Trash by the Delete action in the file browser.
- Show also the file size of the previewed document in the status bar.
- Deprecate the feature to change the editor opacity per window.
- Deprecate the feature of installing a custom theme by simply opening the file in CotEditor.
- Deprecate the “Hiragana to Katakana” and “Katakana to Hiragana” commands in the Text > Transformations menu.
- Deprecate the “Draw separator” option for the line number view on macOS 26.
- [trivial] Rename the “Half-width to Full-width” and “Full-width to Half-width” commands to “Convert to Full Width” and “Convert to Half Width”, respectively.
- [trivial] Improve the behavior of Add/Remove buttons.
- [dev] Migrate the theme list and syntax list in the Settings to SwiftUI.
- [dev] Update the build environment to Xcode 26.0 Beta 6 (Swift 6.2, macOS 26 SDK).
- [non-AppStore ver.] Add an update badge to the “Check for Update” menu item if an update is available.
Full Changelog: 5.2.3...6.0.0-beta