Changes in Thunderbird 84

compose

• The beginNew function now has an optional messageId argument. If messageId is provided, the referenced message is opened to compose as a new message. This works for ordinary messages and templates.

  This change has been backported to Thunderbird 78.7.0.

• Using beginForward function with a forwardInline type and details argument specified has been fixed.

  This change has been backported to Thunderbird 78.7.0.

menus

• The standard properties available to onShown are now available for messages being composed, if your extension has the compose permission.

  This change has been backported to Thunderbird 78.6.0.

tabs

• At start-up, tabs.create will now wait for a window to open before attempting to open a tab.

  This change has been backported to Thunderbird 78.5.0.

windows

• The openDefaultBrowser(url) function has been added.

  This change has been backported to Thunderbird 78.6.0.

browserAction

• The setLabel(details) and getLabel(details) functions have been added. It is now possible to set a label value different from the title (which is used as tooltip text). The label can be set to an empty string to make the action button not have a label at all. If the toolbar is set to text-mode only (no icons), the action button label uses the title as fallback, in case an empty label has been set.

  This change has been backported to Thunderbird 78.6.0.

composeAction

• The setLabel(details, [callback]) and getLabel(details) functions have been added. It is now possible to set a label value different from the title (which is used as tooltip text). The label can be set to an empty string to make the action button not have a label at all. If the toolbar is set to text-mode only (no icons), the action button label uses the title as fallback, in case an empty label has been set.

  This change has been backported to Thunderbird 78.6.0.

messageDisplayAction

• The setLabel(details, [callback]) and getLabel(details) functions have been added. It is now possible to set a label value different from the title (which is used as tooltip text). The label can be set to an empty string to make the action button not have a label at all. If the toolbar is set to text-mode only (no icons), the action button label uses the title as fallback, in case an empty label has been set.

  This change has been backported to Thunderbird 78.6.0.