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/Web Extensions

tabs.Tab

The type tabs.Tab contains information about a tab. This provides access to information about what content is in the tab, how large the content is, what special states or restrictions are in effect, and so forth.

Type

Values of this type are objects. They contain the following properties:

active

boolean. Whether the tab is active in its window. This may be true even if the tab's window is not currently focused.

The active tab is usually the selected one. However, on Firefox for Android, extension popups open in a new tab. When this popup tab is selected, the active tab will instead be the one in which the popup opened.

attention Optional
boolean. Indicates whether the tab is drawing attention. For example, when the tab displays a modal dialog, attention will be true.
audible Optional
boolean. Indicates whether the tab is producing sound. However, the user will not hear the sound if the tab is muted (see the mutedInfo property).
autoDiscardable Optional
boolean. Whether the tab can be discarded automatically by the browser when resources are low.
cookieStoreId Optional
string. The cookie store of the tab. If different tabs can have different cookie stores (for example, to support contextual identity), you can pass this as the storeId option into various methods of the cookies API, to set and get cookies associated with this tab's cookie store. Only present if the extension has the "cookies" permission.
discarded Optional
boolean. Whether the tab is discarded. A discarded tab is one whose content has been unloaded from memory, but is still visible in the tab strip. Its content gets reloaded the next time it's activated.
favIconUrl Optional
string. The URL of the tab's favicon. Only present if the extension has the "tabs" permission or host permissions. It may also be an empty string if the tab is loading.
height Optional
integer. The height of the tab in pixels.
hidden
boolean. Whether the tab is hidden.
highlighted

boolean. Whether the tab is highlighted, i.e. part of the current tab selection. An active tab is always highlighted, but some browsers may allow additional tabs to be highlighted, for example by clicking them while holding Ctrl, Shift or ⌘ Command keys.

Firefox for Android doesn't support highlighting multiple tabs, and Firefox desktop requires the browser.tabs.multiselect preference (enabled by default).

id Optional
integer. The tab's ID. Tab IDs are unique within a browser session. The tab ID may also be set to tabs.TAB_ID_NONE for browser windows that don't host content tabs (for example, devtools windows).
incognito
boolean. Whether the tab is in a private browsing window.
index
integer. The zero-based index of the tab within its window.
isArticle
boolean. True if the tab can be rendered in Reader Mode, false otherwise.
isInReaderMode
boolean. True if the tab is currently being rendered in Reader Mode, false otherwise.
lastAccessed
double. Time at which the tab was last accessed, in milliseconds since the epoch.
mutedInfo Optional
tabs.MutedInfo. The current muted state for the tab and the reason for the last state change.
openerTabId Optional
integer. The ID of the tab that opened this tab, if any. This property is only present if the opener tab still exists and is in the same window.
pinned
boolean. Whether the tab is pinned.
selected
boolean. Whether the tab is selected. This property has been replaced by active and highlighted.
sessionId Optional
string. The session ID used to uniquely identify a Tab obtained from the sessions API.
status Optional
string. Either loading or complete.
successorTabId Optional
integer The ID of the tab's successor.
title Optional
string. The title of the tab. Only present if the extension has the "tabs" permission or host permissions that matches the tab's URL.
url Optional
string. The URL of the document that the tab is displaying. Only present if the extension has the "tabs" permission or a matching host permissions.
width Optional
integer. The width of the tab in pixels.
windowId
integer. The ID of the window that hosts this tab.

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
active
Yes
14
45
?
Yes
14
?
?
54
?
?
?
audible
45
79
45
?
32
14
?
?
54
?
?
?
autoDiscardable
54
79
No
?
41
No
?
?
No
?
?
?
cookieStoreId
No
No
52
?
No
No
?
?
No
?
?
?
discarded
54
79
57
?
41
No
?
?
57-79
?
?
?
favIconUrl
Yes
14
45
?
Yes
No
?
?
No
?
?
?
height
31
79
45
?
18
14
?
?
54
?
?
?
highlighted
Yes
79
45
?
Yes
14
?
?
54-79
?
?
?
id
Yes
14
45
?
Yes
14
?
?
54
?
?
?
incognito
Yes
14
45
?
Yes
14
?
?
54
?
?
?
index
Yes
14
45
?
Yes
14
?
?
54
?
?
?
isArticle
No
No
58
?
No
No
?
?
No
?
?
?
isInReaderMode
No
No
58
?
No
No
?
?
No
?
?
?
lastAccessed
No
No
56
?
No
No
?
?
56
?
?
?
mutedInfo
46
79
45
?
33
14
reason and extensionId will not be populated.
?
?
54
?
?
?
openerTabId
18
79
57
?
15
14
?
?
No
?
?
?
pinned
Yes
14
45
?
Yes
14
?
?
54
?
?
?
selected
Yes
79
45
?
Yes
14
?
?
54
?
?
?
sessionId
31
79
Yes
?
18
No
?
?
No
?
?
?
status
Yes
14
45
?
Yes
14
?
?
54
?
?
?
successorTabId
No
No
65
?
No
No
?
?
No
?
?
?
title
Yes
14
45
?
Yes
14
?
?
54
?
?
?
url
Yes
14
45
?
Yes
14
?
?
54
?
?
?
width
31
79
45
?
18
14
?
?
54
?
?
?
windowId
Yes
14
45
?
Yes
14
?
?
54
?
?
?

Example extensions

Note: This API is based on Chromium's chrome.tabs API. This documentation is derived from tabs.json in the Chromium code.

Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.

© 2005–2021 MDN contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/tabs/Tab