files/en-us/mozilla/add-ons/webextensions/api/tabs/tab/index.md
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.
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_inline}}
boolean. Indicates whether the tab is drawing attention. For example, when the tab displays a modal dialog, attention will be true.audible {{optional_inline}}
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_inline}}
boolean. Whether the tab can be discarded by the browser. The default value is true. When set to false, the browser cannot automatically discard the tab. However, the tab can be discarded by {{WebExtAPIRef("tabs.discard")}}.cookieStoreId {{optional_inline}}
string. The cookie store of the tab. See Work with contextual identities for more information.discarded {{optional_inline}}
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_inline}}
string. The URL of the tab's favicon. Only present if the extension has the "tabs" permission or host permissions. It may also be undefined if the page has no favicon, or an empty string if the tab is loading.groupId {{optional_inline}}
integer. The ID of the tab group the tab belongs to. Set to -1 ({{WebExtAPIRef("tabGroups.TAB_GROUP_ID_NONE")}}) if the tab doesn't belong to a tab group. See {{WebExtAPIRef("tabs.group")}}. For more information on tab groups, see {{WebExtAPIRef("tabGroups")}}.height {{optional_inline}}
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 <kbd>Ctrl</kbd>, <kbd>Shift</kbd> or <kbd>⌘ Command</kbd> keys.
Firefox for Android doesn't support highlighting multiple tabs.
id {{optional_inline}}
integer. The tab's ID. Tab IDs are unique within a browser session. The tab ID may also be set to {{WebExtAPIRef('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 {{optional_inline}}
double. Time at which the tab was last accessed, in milliseconds since the epoch.mutedInfo {{optional_inline}}
openerTabId {{optional_inline}}
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.pendingUrl
string. The URL the tab is navigating to, before it has committed. This property is only present if the extension's manifest includes the "tabs" permission and there is a pending navigation.pinned
boolean. Whether the tab is pinned.selected {{deprecated_inline}}
boolean. Whether the tab is selected. This property has been replaced by active and highlighted.sessionId {{optional_inline}}
string. The session ID used to uniquely identify a Tab obtained from the {{WebExtAPIRef('sessions')}} API.splitViewId {{optional_inline}}
integer. The ID of the split view the tab belongs to. Set to {{WebExtAPIRef('tabs.SPLIT_VIEW_ID_NONE')}} when the tab doesn't belong to a split view.status {{optional_inline}}
string. Either loading or complete.successorTabId {{optional_inline}}
integer The ID of the tab's successor.title {{optional_inline}}
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_inline}}
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_inline}}
integer. The width of the tab in pixels.windowId
integer. The ID of the window that hosts this tab.{{WebExtExamples}}
{{Compat}}
<!-- // Copyright 2015 The Chromium Authors. All rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are // met: // // * Redistributions of source code must retain the above copyright // notice, this list of conditions and the following disclaimer. // * Redistributions in binary form must reproduce the above // copyright notice, this list of conditions and the following disclaimer // in the documentation and/or other materials provided with the // distribution. // * Neither the name of Google Inc. nor the names of its // contributors may be used to endorse or promote products derived from // this software without specific prior written permission. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -->[!NOTE] This API is based on Chromium's
chrome.tabsAPI. This documentation is derived fromtabs.jsonin the Chromium code.