Supported UI Elements
Descriptions and examples of MailExtension APIs to interact with Thunderbird's user interface.
A browser action adds a button to Thunderbird's main toolbar:
It is controlled by the
browser_action manifest key in the extension's manifest.json file:"browser_action": {
"default_title": "Restart",
"default_icon" : "restart.png",
"default_popup": "browser_popup.html"
},
If a
default_popup is defined, a popup will be opened and the defined html page will be loaded, when the button is clicked. Additionally, you can use the browserAction API in your background script to interact with the button to modify badge text, icon, title or its enabled state.A compose action adds a button to the toolbar of the composer window:
It is controlled by
compose_action manifest key in the extension's manifest.json file:"compose_action": {
"default_title": "Expand lists",
"default_icon" : "lists.png",
"default_popup": "compose_popup.html"
},
If a
default_popup is defined, a popup will be opened and the defined html page will be loaded, when the button is clicked. Additionally, you can use the composeAction API in your background script to interact with the button to modify badge text, icon, title or its enabled state.A message display action adds a button to the toolbar of the message view window:
It is controlled by the
message_display_action manifest key in the extension's manifest.json file:"message_display_action": {
"default_title": "Copy Patch",
"default_icon" : "patch.png",
"default_popup": "message_popup.html"
},
If a
default_popup is defined, a popup will be opened and the defined html page will be loaded, when the button is clicked. Additionally, you can use the messageDisplayAction API in your background script to interact with the button to modify badge text, icon, title or its enabled state.Thunderbird supports cloud providers to upload large attachments to a server, instead of attaching them directly to the email. Extensions can register such cloud providers using the
CloudFile API. These providers can be managed in Thunderbird's Composition options:
The
menus API allows modifying Thunderbird's menus by adding or overriding menu items. The menu items can be added to different menus based on the provided context type. The following values are currently supported:all | All allowed contexts, excluding tab. |
all_message_attachments | Context menu on the summary of the message attachments.
 message_attachments context is used instead. |
browser_action, compose_action , message_display_action | Context menu of action buttons.
 |
compose_attachments | Context menu of attachments in the compose window.
 |
editable,
password | Context menu of text/password input fields in WebExtension windows, web tabs or message display tabs.
Limited to content areas.
 |
folder_pane | Context menu of the folder pane of mail tabs. Not limited to a folder entry.
 |
image,
audio,
video | Context menu of embedded images, audio or video players in WebExtension windows, web tabs or message display tabs.
Limited to content areas.
 |
link | Context menu of links in WebExtension windows, in web tabs or in message display tabs.
Limited to content areas.
 |
message_attachments | Context menu of a single message in the attachments area.
 |
message_list | Context menu of the message list area of a mail tab. Not limited to a message list entry.
 |
page,
frame | Context menu of WebExtension windows, web tabs or message display tabs, if none of the other content contexts apply (link, selection, image, audio, video, editable, password).
If the page is loaded inside a frame, the frame context applies, otherwise the page context.
Limited to content areas.
 |
selection | Context menu in WebExtension windows, web tabs or message display tabs, if any text has been selected.
Limited to content areas.
 |
tab | Context menu of tab ribbons.
 |
``
Last modified 16d ago