Mailspring

1.23.0 (7/19/2026)

Features:

• Added Office 365 shared mailbox support. (#2763) Thanks @Kevin-Hamilton!
• Added the ability to export folders to mbox files. (#2765) Thanks @Kevin-Hamilton!
• Added an option to count unread messages across all accounts. (#2779) Thanks @WebDevBar!
• Added a toggle for email render mode. (#2737) Thanks @AidanWarner97!
• Added an MCP server (off by default) that lets local agents interact with mail.
• On Linux, added a taskbar unread badge for KDE and other non-Unity desktops. (#2756) Thanks @WebDevBar!

Bug Fixes:

• Fixed a composer crash on quoted emails with inline images. (#2776)
• Fixed a composer crash when grammar-check decorations apply mid-composition. (#2775)
• Fixed missing Slate attributes on the IMAGE_TYPE fallback node. (#2774)
• Fixed a composer cut crash and suppressed Sentry noise from third-party plugins. (#2755)
• Fixed a crash when dragging threads to the sidebar after a thread is deleted. (#2760)
• Fixed a crash in EventRSVPTask when attendee ICS data goes stale. (#2770)
• Fixed a crash in the translation plugin when the iframe contentDocument is not yet loaded. (#2752)
• Fixed an onboarding crash when back-navigation empties the page stack. (#2750)
• Fixed navigator.clipboard.writeText in @electron/remote MenuItem handlers. (#2754)
• Fixed an ERR_FILE_NOT_FOUND crash in Show Original when the RFC822 fetch fails. (#2772)
• Fixed null crashes in SendDraftTask, thread-sharing, and send-and-archive. (#2757)
• Fixed a null crash in three IPC handlers when BrowserWindow.fromWebContents() returns null. (#2758)
• Fixed cancellation of GetManyRFC2822Task (folder export). (#118) Thanks @Kevin-Hamilton!
• Fixed handling of XDG paths. (#2761) Thanks @LinusDierheimer!
• On Linux, fixed an EPIPE crash loop in the uncaughtException handler. (#2769)
• On Linux, send org.freedesktop.DBus.Hello before emitting the badge signal. (#2778) Thanks @WebDevBar!
• Stopped startup after a fatal config.json load failure. (#2764)
• Guarded nativeTheme remote object access in SystemTrayIconStore. (#2753)
• Guarded grammar check so it no longer emits warnings when logged out.

Improvements:

• Added a macOS 27 icon variant.
• Reduced Sentry noise: expected IMAP/SMTP auth and connection failures are no longer reported. (#2762)
• Reduced Sentry noise from OAuth SSL failures and improved the mailsync crash message. (#2771)
• Downgraded the unknown-feature warning from an error report to a console warning. (#2759)
• Wrapped unhandled fetch errors in APIError in makeRequest. (#2766)
• Fixed an uncaught 'error' event crash in MailsyncProcess.sync(). (#2773)
• Fixed an unhandled rejection in IdentityStore background polling. (#2768)

Developer:

• Upgraded @electron/packager to prevent build hangs on newer Node.js versions. (#2767) Thanks @wrench-exile-legacy!
• Get the desktop name dynamically from package.json and stop hardcoding Mailspring.desktop. (#2748, #2777) Thanks @LinusDierheimer!
• Use a template var as the icon value in Mailspring.desktop. (#2747) Thanks @LinusDierheimer!
• Added branding colors to appdata.xml. (#2751) Thanks @LinusDierheimer!
• Fall back to ad-hoc signing in the copy-to-app build phase. (#117) Thanks @Kevin-Hamilton!

Features:

• Added the ability to choose which themes apply in automatic light/dark mode. (#2732) Thanks @Jayphen!

Bug Fixes:

• Fixed null crash when clicking "Send now" on undo-send toast after the message had already been sent. (#2738)
• Fixed two null-access crashes reported in Sentry (MAILSPRING-CLIENT-1G, MAILSPRING-CLIENT-18, MAILSPRING-CLIENT-2V). (#2740)
• Fixed two Sentry crashes: null account in preferences and null window in app menu IPC. (#2741)
• Fixed crash when archiving from search with label-based archive categories. (#2743)
• Fixed null crash when removing threads with unsynced trash/archive category. (#2736)
• Fixed Outlook account setup. (#2735) Thanks @Suchiman!
• Fixed Windows print crash caused by invalid file URL. (#2733)
• Fixed TOCTOU null-reference crash in draft body setter (MAILSPRING-CLIENT-S). (#2728)
• Fixed DefaultClientHelperMac passing boolean to error callback, causing false Sentry reports. (#2731)
• Fixed AttributeDateTime.fromJSON treating 0/falsy values as missing. (#2730)
• Fixed quickpreview CSP clobbering the default session's app-wide CSP. (#2744) Thanks @dansleboby!
• Fixed QuerySubscription._fetchRange contiguity check using actual result length. (#2734)
• On Windows, fixed EPERM crash when forking background query agent. (#2745)

Improvements:

• Improved Microsoft OAuth: better email resolution and suppressed no-mailbox errors from Sentry. (#2746)
• Added diagnostics around "draft not found" error on send and cleaned up waiting queues. (#2727)
• Moved payment flow out of modal to launch on the web for newer Stripe integration.
• Richer exceptions when account has no from address or when label is provided to ChangeFolderTask.
• Draft reminders now use thread: metadata prefix so sync engine promotes them to thread on send. (#2729)
• Sync engine now forwards identity-level refresh events from delta stream. (mailsync#115)

Performance:

• Optimized search regex compilation in category and label pickers. (#2715)
• Improved sync engine performance by reducing unnecessary SQLite writes and moving parsing outside transactions.

Bug Fixes:

• Improved theme support in calendar
• Fixed dark mode email bodies not reflecting the system tint color.
• Fixed activeMarks access errors in the composer editor. (#2714)
• Fixed thread list scroll indicator not sliding through time when dragging the scroll handle. (#2716)
• Fixed contains error when parentFilter receives a non-Element node. (#2712)
• Fixed secrets potentially appearing in the connection error detail modal. (#2717)
• Fixed package name validation rejecting names with uppercase letters. (#2718)
• Fixed sync engine crash during many-account sync by increasing SQLite busy timeout.
• Fixed message importance headers not normalized for compatibility with some providers. (mailsync#113)
• Improved error logging for empty or malformed error objects. (#2713)

Developer:

• Upgraded Electron from 41.5.0 to 41.6.1.
• Upgraded React and React DOM to v17. (#2725)
• Upgraded react-transition-group from 1.2 to 4.4.5.
• Replaced deprecated componentWillMount with componentDidMount. (#2724)
• Replaced legacy context API with React Context. (#2722, #2723)
• Refactored class components to functional components with React.memo. (#2720)
• Removed PropTypes, replaced with TypeScript types. (#2710)
• Added missing TypeScript types to function declarations across many files.
• Renamed remaining package spec directories to specs, converted JSX to TSX. (#2711)
• Added Playwright tests for composer interactions.
• Fixed lint CI step that was performing fixes instead of validation. (#2719)
• Removed unused CircleCI configuration.
• Set C++ standard to C++17 across all platforms. (mailsync#114)
• Various CMake and build improvements for mailsync. (mailsync#108, mailsync#109, mailsync#110, mailsync#111, mailsync#112) Thanks @LinusDierheimer!

Features:

• Added Reply-To field to the composer header, allowing you to specify a different reply address when composing messages. (#2691) Thanks @Argjend12345!

• Added bulk RFC2822 message export functionality to the sync engine. (#107)

Bug Fixes:

• Fixed HTTP/2 framing errors that could crash the sync engine during metadata streaming. (#103)

• Prevented global keyboard shortcuts from firing when focus is in the composer. (#2693)

• Strictly validate accent color hex values from system preferences to prevent errors. (#2692)

Claude Security Audit:

• Tightened validation to prevent file:// URIs in email content. (#2699)

• Limited path traversal in protocol handler. (#2700)

• Added allowlist validation for IPC window and webcontents methods. (#2701)

• Improved HTML sanitization in the composer when pasting content. (#2702)

• mailto links no longer support the ?attach= query parameter. (#2703)

• Improved attachment name sanitization for security and compatibility. (#2705)

• Improved email sanitization to block CSS @import tracking vectors. (#2706)

• Added package name validation to prevent path traversal attacks. (#2698)

• Added URL validation to the autoupdate handler. (#2697)

• Show a notice about plugin trust when installing third-party plugins.

Improvements:

• When a detailed error log is available during OAuth sign-in, it is now displayed to help with troubleshooting.

• Used exec in mailsync wrapper script for direct signal delivery. (#105)

Developer:

• Migrated build system from Grunt to a standalone Node.js script. (#2704)

• Added option to skip installer creation in the build script. (#2707) Thanks @LinusDierheimer!

• Dropped .map files from distribution packages. (#2686) Thanks @ReillyBrogan!

• Replaced long-deprecated Raven with native Sentry envelope implementation and send sourcemaps during build. (#2694)

• Upgraded TypeScript target from es2017 to es2024.

• Refactored TypeScript compilation cache and only enable in dev mode. (#2695)

• Removed macOS Touch Bar support. (#2696)

• Updated ESLint and Prettier, and reference local versions in VS Code settings.

• Added missing TypeScript types to function declarations across many files.

• Upgraded Electron 41.2.1 to Electron 41.5.0.

• Added Playwright tests for pre-release verification.

• Added tests covering VCF/EML business logic and other utilities.

Fixes:

• Resolves an issue with the inline composer's key handling that could cause Gmail-style shortcuts to activate while you were typing into the subject line or recipients.

Features:

• Added an "Automatic" theme (the new default) that follows system light/dark mode.

• Added system accent color support — the standard light and dark themes now use your OS accent color by default and this can be disabled from Preferences > Appearance. (#2682)

• Improved the UX around creating folders and labels in the left sidebar - it's much easier to create nested items. (#2655)

• A new "•••" menu on items in the left sidebar makes features (including the new EML export option) more discoverable.

• Added EML export functionality for messages and folders. You can save selected messages as EML by right-clicking or from the app's menu, and export entire folders by right clicking in the left navigation. (#2652)

Improvements:

• Improved password storage error handling and reporting. (#2669)

• Fixed a race condition causing Windows notification "Archive" and "Mark as Read" buttons to be unreliable.

• Added Microsoft Office 365 / Outlook account setup guidance and troubleshooting documentation. (#2656)

• Replaced text symbols with SVG icons in the toolbar. (#2658)

• Refinements to EML export task in the sidebar.

• Fixed the Wayland app_id after Electron 41 (Thanks @ReillyBrogan!)

Bug Fixes:

• Fixed an undefined @font-weight-semi-bold error in the ui-less-is-more theme. (#2684)

• Fixed a crash in quick preview when the capture window is destroyed. (#2671)

• Fixed an unhandled EPIPE error when writing to a dead mailsync process stdin. (#2673)

• Fixed race conditions in draft expiration and changeset handling. (#2678)

• Fixed broken IMAP UTF-7 encoding by replacing the broken utf7 package with a custom implementation. (#2672)

• Fixed printToPDF errors being incorrectly sent to Sentry. (#2677)

• Fixed an issue where launch options and URLs were processed before app initialization was complete. (#2675)

• Fixed a crash caused by null values in draft field change detection. (#2676)

• Fixed an issue where metadata attachment could fail for newly sent messages. (#2664)

• Fixed autoupdate error handling. (#2670)

• Fixed error handling for ICS parsing in the EventHeader component. (#2668)

• Fixed crash when navigating to 'All' with accounts that have no archive category. (#2666)

• Fixed null reference crash in ContactDetail on update. (#2661)

• Fixed MacOS notifications showing a second copy of the app's icon

• Fixed null range crash in the email composer. (#2662)

• Fixed a race condition in EmailFrame that could deliver a null doc.body to message extensions. (#2665)

• Fixed OAuth code parsing to handle + characters correctly. (#2654)

• Fixed the core:pop-sheet shortcut being blocked in the message list with an open reply composer. (#2653)

• On Windows, fixed font-weight rendering by using CSS variables. (#2650)

• On Linux, fixed xdg-mime 'not found' error not being caught on dash-based shells. (#2667)

• Added error handling for shell.openExternal calls to prevent crashes on unsupported URLs. (#2679)

Developer:

• Fixed ability to declare platform-specific options via config-schema. (#2681)

• Moved appdata.xml to the metainfo directory for proper Linux packaging. (#2659) Thanks @BlueManCZ!

• Replaced direct Electron dialog.showErrorBox calls with AppEnv.showErrorDialog. (#2680)

• Improved plugin activation error handling and TypeScript compilation. (#2674)

• Suppressed LESS parse errors from Sentry reporting. (#2663)

Bug Fixes:

• On Windows, fixed notification click handling and removed a redundant window display call. (#2648)

• Fixed the custom port input not updating in IMAP onboarding. (#2646)

• Fixed VoiceOver handling on email composer token inputs (To, CC, BCC, etc.).

Improvements:

• Additional accessibility improvements: arrow key navigation and roving tabindex between messages in the message list, keyboard focus improvements in the account sidebar, email frame ARIA target for read-all support, and focus management fixes for modals and preferences.

• On Linux, added Wayland session detection and a fallback menu button for window managers that don't support the system tray. (#2647)

• Improved handling of navigation keys (arrow keys, etc.) in the composer typing state. (#2644) Thanks @ejbiker93ss!

• Improved contact details panel styling.

• On Linux/Wayland: frameless windows now display GTK drop shadows and support extended resize borders

Developer:

• Updated to Electron 41 (Chromium 146, Node.js 24.14), up from Electron 39 (Chromium 142, Node.js 22). (#2643)

  • Chromium updated from 142 → 146, bringing security patches and modern web standard support
  • Fixed white flash when opening app windows
  • Reduced GPU memory usage on macOS
  • On Windows: fixed a crash with UTF-8 file paths and a hang in native notification delivery
  • On macOS: fixed menu items incorrectly staying disabled after being re-enabled
  • On Windows: fixed window fullscreen state not being preserved correctly
  • On Windows: system notifications now support action buttons and inline reply inputs
  • Fixed keyboard shortcut accelerators not working after toggling a menu item's enabled state
  • Replaced the deprecated Electron clipboard renderer API with the standard navigator.clipboard API

• Replaced legacy dependencies (fs-plus, rimraf, mkdirp, uuid, temp) with native Node.js APIs, removing several third-party dependencies.

• Removed unused dependencies deep-extend and graceful-fs.

• Added TypeScript typecheck and lint steps to the per-commit GitHub Actions workflow.

• Updated license dates.

Features:

• Comprehensive accessibility improvements, including semantic landmarks, ARIA attributes, focus traps for modals, accessibility labels on buttons, and more. If you use Mailspring using a screenreader, we'd love feedback about this release. (#2638)

• Added VCard import/export functionality to contacts. (#2626)

• Added support for creating new calendar events via double-click on the calendar. (#2635)

• Added Calendar menu and keyboard shortcuts. (#2634)

Bug Fixes:

• Fixed a TypeError when a contact's birthday date is undefined. (#2632)

• Fixed Windows app restart and update handling with Squirrel. (#2631)

• Fixed canBeUndone initialization in ChangeMailTask subclasses. (#2630)

• Gracefully handle xdg-mime not being present on some Linux machines.

• Fixed poor Sentry reporting of errors bridged over the report-error IPC channel.

• Fixed an "Invalid String Length" error in the mailsync-process wrapper on very large stderr output.

• Fixed a CardDAV issue with headers on XML requests and empty multiget responses.

• Fixed ERR_ABORTED errors from quick previews being silently reported to Sentry.

Improvements:

• Improved calendar event editing with ICS-based recurrence support. (#2637)

• Added recurring event indicator icon to calendar events. (#2633)

• Added tray icon theme picker and 'none' style option for Linux. (#2628)

• Tuned thread list swipe gesture detection, and added an option to disable swipe gestures. (#2629)

• Folded grammar check preferences into General > Composer. (#2639)

• Improved emoji popover positioning and updated emoji artwork with new additions.

• Recovered the Slate editor when the user selects all and deletes all text, leaving only quoted text.

• Added WSAGetLastError() logging for TCP connection failures on Windows (mailsync).

Developer:

• Added X-GNOME-UsesNotifications=true to the Linux .desktop file. (#2640) Thanks @LinusDierheimer!

• Added vcs-browser to the Linux AppStream metadata. (#2641) Thanks @LinusDierheimer!

• Removed deprecated Electron 4 polyfills and other outdated TODOs. (#2636)

• Moved tests to @testing-library/react, run in GitHub Actions.

• Added community plugins and themes documentation. (#2627)

Features:

• Grammar check is now available in the composer! (#2612)

  • This feature relies on a deployment of LanguageTool at id.getmailspring.com - when you use Grammar Check, small snippets of your draft are sent to this server, but the requests are not logged and no message data is stored.
  • This feature is disabled by default. To turn it on, click the new icon in the composer toolbar.

• Mailspring now properly detects "Do Not Disturb" status on MacOS Sequoia and on Windows.

Bug Fixes:

• On Wayland, the --background flag now shows the main window briefly then hides it, which is the best we can do under Wayland's rules. (#2623)

• On Wayland, fixed a keyboard freeze in the composer caused by a double focus() call. (#2622)

• Fixed sound notifications playing on Windows regardless of the notification preference. (#2619)

• Fixed the tray icon theme detection on GNOME/Unity Linux desktops. (#2610)

• Fixed a crash in vCard parsing when the VERSION line is not found.

• Fixed an issue with the first CardDAV sync incorrectly seeing existing ETags in mailsync.

• Fixed IMAP IDLE to process VANISHED notifications sent by FastMail (and possibly other providers).

• Fixed folder priority logic that was incorrectly applied to non-iCloud accounts in mailsync.

Improvements:

• Added support for the stnadard biographies / notes field on contacts. (#2621)

• Rearranged the thread context menu to reduce accidental destructive actions. (#2620)

• Added an empty state to the calendar when no CalDAV accounts are connected. (#2625)

• The draft window now uses the message subject as the window title.

• Improved read receipt tracking pixel reliability. (#2613)

• Improved mail rules robustness and fixed condition evaluation bugs. (#2616)

• Added VTIMEZONE to created calendar events so they are created on Yahoo in the correct timezone.

• Enabled CalDAV discovery to support Fastmail, Yahoo, and other providers in the upcoming calendar.

• On Windows, the app icon is now a rounded square to better fit with Windows 11 design guidelines.

Developer:

• Replaced CSS-based platform hiding with React conditionals in preferences. (#2614)

• Removed subpixel-antialiased font smoothing overrides. (#2618)

• Added syncInit to main-calendar to eliminate a 2.5s startup delay. (#2606)

Features:

• Added Agenda view to the calendar for chronological event browsing. (#2592)

• Added Linux Do Not Disturb detection for notification suppression. (#2595)

• Added Windows jump list and badge icon desktop integration. (#2594)

• Added ARM64 (aarch64) Linux build support. (#2601)

• The selected calendar view now persists across sessions. (#2600)

Bug Fixes:

• Fixed support for Wayland - window activation context is now handled gracefully. (#2599)

• Fixed the app's system tray icon appearing as three dots (•••) at launch on Ubuntu 25.

• Fixed summary notifications: broken Windows toast URLs and race condition. (#2597)

• Improve Yandex account sync by ignoring their XLIST implementation, which is known to be buggy.

• Fixed mutex re-entry locks during exception handling in mailsync that could be hit if a network disconnect caused both sync workers to throw at the same time.

• Reverted IDLE error suppression that caused sync issues.

Improvements:

• On Linux, default to thin window framing with hamburger-style right menu. (#2604)

• On Linux, added dark/light system tray icon support. (#2602)

• Improved JS algorithm performance using Map/Set for better collection handling. (#2596)

• Enabled support for custom config directory path. (#2587) Thanks @DerDemystifier!

• Added missing release info in appdata. (#2586) Thanks @ychavoya!

Developer:

• Updated node-abi to 3.87.0 and added support for prebuilt better-sqlite3 binaries. (#2598)

• Signed native .node addon files for Smart App Control compliance. (#2589)

• Fixed RPM packaging dependencies for Fedora 43 and openSUSE compatibility. (#2590)

• Fixed openSUSE CI test and RPM post-install scriptlet issues. (#2591)