
### Bug Fixes

* address code review findings across sync, tasks, and UI (#6339)
* **backup:** support importing pre-v17 backups (v10-v15 tested, v16 partial) (#6271)
* **build:** update glob API and remove unused Angular imports
* **build:** use Apple continuous-corner bezier curves for mac icon squircle
* **config:** make clipboardImages optional for backwards compatibility
* **e2e:** correct case-sensitive switch labels in app-features tests
* **e2e:** reduce flakiness and speed up WebDAV sync tests
* **e2e:** stabilize undo task delete sync test
* **e2e:** use desktop selectors for simple counter sync tests
* **e2e:** use specific heading locator in plugin loading test
* **focus-mode:** stop time tracking when exiting break to planning
* **habit-tracker:** remove unused MsToStringPipe import
* **inline-markdown:** preserve unsaved content when adding checklist item
* **inline-markdown:** update placeholder and modelCopy to use empty string instead of `undefined` string (#6281)
* **main-header:** center sync icon glyph to eliminate spin wobble (d74ab29), closes #6318
* **main-header:** remove unnecessary right padding on macOS Electron (a5c6337), closes #6337
* **main-header:** restore inline simple counter buttons on desktop
* **schedule-week:** adjust sizes (#6350)
* **sync:** add explicit error handling for UTF-8 decoding in iOS WebDAV plugin
* **sync:** add isWaitingForUserInput$ guard to strict initial sync timeout
* **sync:** add native iOS WebDAV plugin to fix broken read on iPhone (fcedc4e), closes #6317
* **sync:** add retry logic for transient iOS network errors in Dropbox sync (39eaef7), closes #6333
* **sync:** address code review findings for archive-wins and entity frontier
* **sync:** address code review findings for E2E tests and sync services
* **sync:** archive-wins pre-scan and entity frontier for new clients
* **sync:** clean up review findings from TOCTOU race fix
* **sync:** eliminate TOCTOU race in duplicate operation detection (#6343)
* **sync:** handle concurrent ops for archived/deleted entities
* **sync:** handle MultiEntityPayload in LWW Delete vs Update conflict resolution
* **sync:** improve conflict resolution fallback path and fix duplicate CSS var
* **sync:** prevent Formly from clearing provider config on show (#6345)
* **sync:** prevent lost piggybacked ops and worklog crashes during multi-client sync
* **sync:** prevent recurring task duplication across clients
* **sync:** prevent task duplication during file-based sync snapshot hydration
* **sync:** remove dead code, add defensive checks, and clean up vector clock logic
* **sync:** restore WebDAV provider compatibility warning text
* **tasks:** clear remindAt when rescheduling task via planner (#6342)
* **tasks:** correct biweekly recurring task week boundary calculation (#6298)
* **tasks:** detect and sanitize orphaned task IDs to prevent startup crashes (#6359, #6360)
* **tasks:** filter orphan IDs in removeTasksFromTodayTag reducer (#6327)
* **tasks:** filter undefined entities in selectAllTasks to prevent crashes
* **tasks:** filter undefined subtasks in mapSubTasksToTask (#6325)
* **tasks:** fix huge space between emoji and text in tag/project menus (bfce556), closes #5977
* **tasks:** guard against undefined entities in work-context selectors (#6357)
* **tasks:** guard against undefined task entities in selectors and archive (#6359)
* **tasks:** guard against undefined task in mainListTasksInProject$ (#6360)
* **tasks:** handle compound emojis in icon input using Intl.Segmenter
* **tasks:** prevent recurring tasks from failing to repeat (#6192)
* **tasks:** reset devError state in orphan ID detection test
* **test:** add missing skipConflictDetection arg in forceDownloadRemoteState test
* **test:** add skipSpinnerCheck to USE_REMOTE waitForSyncToComplete calls
* undefined redmine ticket (#6279)
### Features

* add Czech, Slovak, and Ukrainian calendar locale support and correct Czech language code from 'cz' to 'cs'. (#6329)
* **simple-counter:** add isHideButton config to hide toolbar button
* **sync:** add rolling JWT token refresh on sync requests
* **sync:** mark WebDAV and LocalFile sync options as experimental
* **theme:** add Cybr. New THEME (#6314)
### Performance Improvements

* **sync:** restore fast SuperSync startup while preventing repeat task duplication
* **test:** speed up slow encryption and large batch sync tests
### Reverts

* Revert "feat(sync): add rolling JWT token refresh on sync requests"