REMINDER: Postbox 7 contains several font fixes that may require new font sizes to be set.

Postbox 7.0.2

  • Added monochrome icons to the Address Book sidebar for themes that support them
  • Fixed an issue with fonts not picking up the correct color in the Address Book on Windows
  • Fixed an issue that prevented with content display after a delete action when an Account Group was selected

Postbox 7.0.1

  • Search bar dropdown menu now inherits theme styling
  • Messages will now reload when switching between light and dark themes
  • Fonts have been made darker on many of the themes
  • Corrected letter spacing for the San Francisco font on MacOS 10.15 Catalina
  • Changed the background color of the Filter Log
  • We now display the proper placeholder message when "Search All Folders" is selected without a search term
  • Fixed an issue that could cause the “Default” theme to not display correctly when the OS was in light mode
  • Fixed an issue that could prevent a default Clip from being set on alternate Identities

Postbox 7.0

What's New


Postbox now ships with 20 beautiful themes spread across light and dark modes. To select a new theme, click the Themes button in the toolbar or select a theme from the View > Theme menu.

The "Default" option will automatically switch between the original "Light" and "Dark" themes based upon the OS preference or dark mode state.


Clips let you quickly insert pre-formatted blocks of HTML into your messages. It works similarly to Responses and Signatures, but Clips have two additional capabilities:

  1. Clips can insert CSS into the <head> region of a message
  2. A default Clip can be used per identity when new messages are composed

This means that you can now create sophisticated newsletters, brand templates, or stationary and use them as needed or by default per identity.

Theoretically, any email template that you can create or find on the web can now be used in Postbox.

Like Signatures and Responses, we've included a suite of example Clips that you can use in your messages, including:

  • checked bullets
  • numbered bullets
  • buttons
  • callouts
  • description list
  • horizontal rules
  • image blocks
  • quotes
  • social follow blocks
  • text blocks
  • tables

To access Custom Clips, open the Compose window, make sure the Clips button is added to the Toolbar, press and hold the Clips button, then select Custom Clips from the menu.


Similar to add-ons, our Labs feature will allow for experimental 3rd-party code to be used within Postbox.

The first Labs project will be OpenPGP support provided by a specially designed version of Enigmail for Postbox and can be enabled under the Tools menu (remember to add the appropriate buttons to the Compose window toolbar).

Unlike add-ons which can be arbitrarily installed, only a select number of Labs projects will be available for Postbox. Given that Labs projects contain 3rd-party experimental code, they are not officially supported by Postbox, Inc.

If there's a 3rd-party solution you would like to see in Postbox, contact the 3rd-party developer directly. Please do not contact Postbox asking us to support code we do not develop, thanks! 👍

Cloud File Sharing for Business

By popular demand, we've added two new services to our Cloud File Sharing feature:

  • Dropbox for Business
  • OneDrive for Business

New Swipe Gestures on macOS

We've created a new swipe mechanism on macOS that will provide better feedback for four commonly used actions:

  • 1/2 swipe left = Archive
  • full swipe left = Reminder
  • 1/2 swipe right = Junk
  • full swipe right = Delete

The swipe actions work on a "swipe-n-hold" basis. Swipe until the desired action is displayed, hold, then let go once the swipe action "activates." This usage pattern was designed to prevent accidental swipes from performing an action.

Most importantly, swipe actions can be performed on multiple messages at once!

Currently, this feature is available on macOS only.

Quick Copy

This works similarly to Quick Move but copies the message to the desired folder instead of moving it. The keyboard shortcut "c" will bring up the Quick Bar, and from there you can type the name of the folder you wish to copy the message to.

Gmail Labeling Mechanism

We've created a new mechanism for Gmail labeling that mirrors the actions used for Quick Move, Quick Switch, and Quick Copy. Type the "l" key to bring up the Quick Bar, then autocomplete against the desired label name.

Gmail labeling works similarly to Topic assignment in the Quick Bar, and you can now assign multiple labels at once.

Highlight & Strikethrough in Compose

The compose formatting toolbar now supports text strikethrough and highlighting.

New Filter Actions

We've added three more filter actions:

  • Add Prefix to Subject
  • Add Suffix to Subject
  • Add Sender to Address List
Other Improvements
  • Improved Gravatar Support
  • Date Pickers in the Search Bar
  • Alphabetical sorting of Topics in the editor panel
  • vCards can now be imported to the Address Book by double-clicking on them
  • Improved styling for vCard display
  • Improved status messages in the preview pane
  • Added option and set default to limit Conversation View to messages in the Inbox, Sent, and Archive folders in Preferences | Options > Display > Conversations
  • Added Quick Post actions to the Quick Bar with the keyboard shortcut “q”
  • Multiple selected messages now display a message count in the preview area
  • Added OAuth2 (Yahoo) to the account settings page
  • Implemented preference to hide/show signatures in conversation view
  • Improved the options for remote image loading
  • Improved icon display when using different resolutions on Windows
  • Implemented TCP keepalive option to improve connections
  • Added preference to MIME encode 8-bit headers to fix Yahoo character and question mark issues
Changes in Behavior
  • Removed the default preference for composition background color
  • Changed font sizes from points to pixels in the compose window, which may require that you change your default composition size
  • Increased line-height for composition and display
  • Changed delete behavior for Google accounts to better mirror what Gmail does on the web
Bug Fixes
  • Fixed an issue that could cause URLs with line breaks in them to not open in a browser
  • Fixed an issue that could cause messages to not be Marked as Read after deleting when the Preview Pane is closed
  • Fixed an issue that could prevent child messages from being selected when the message preview pane is closed
  • Fixed an issue when contextual-clicking non-selected messages and performing actions, the selector didn’t return to the previously selected message
  • Fixed an issue when contextual-clicking non-selected messages and performing actions, the action would be performed on the previously selected message
  • Fixed an issue when the default send server was not being respected when clicking on an email address in the contact card
  • Fixed an issue when using arrow keys to select contacts in the addressing auto-complete widget
  • Fixed an issue that could cause sort order to get reset after a file or image search
  • Fixed an issue that could cause the Task Bar icon to reset during updates on Windows
  • Fixed an issue that could cause duplicate .ics file icons to display
  • Fixed an issue with the Account Wizard where accounts were not recognized as Yahoo accounts
  • Fixed an issue that wouldn’t allow multiple messages to be set as Reminder at once
  • Fixed an issue with addressing messages from the Compose Sidebar recent contacts list
  • Fixed an issue where image attributes were not preserved when selecting a different image during message composition
  • Fixed an issue to prevent files stored in the clipboard to be added during a drag and drop action in the Compose window
  • Fixed a crash that could occur when parsing attachments
  • Fixed an issue with scam detection connectivity
  • Fixed an issue that caused excess CPU while Postbox was at rest and not actively indexing
  • Fixed an issue that could cause read receipts to not display
  • Fixed an issue that could prevent attachments from displaying
  • Fixed a regression that prevented Spotlight from indexing messages on macOS
  • Fixed an issue where selected attachments in compose would not deselect when clicking in the message body
  • Fixed an issue where messages forwarded as attachment contained the wrong display name
  • Fixed an issue that would prevent addressing autocomplete if Gravatar was turned off
  • Fixed an issue that caused avatars to duplicate in the Compose Sidebar if Gravatar was turned off