You can use this API to modify and rearrange tab groups in the browser. Use the chrome.tabGroups API to interact with the browser's tab grouping system. This allows your extension to handle keystrokes, set the composition, and manage the candidate window. Use the API to implement a custom IME for Chrome OS. Use the chrome.idle API to detect when the machine's idle state changes. Use the chrome.identity API to get OAuth2 access tokens. Use the chrome.i18n infrastructure to implement internationalization across your whole app or extension. To override the history page with your own version, see Override Pages. You can add, remove, and query for URLs in the browser's history. Use the chrome.history API to interact with the browser's record of visited pages. Use chrome.gcm to enable apps and extensions to send and receive messages through the Google Cloud Messaging Service. Use the chrome.fontSettings API to manage Chrome's font settings. Use the chrome.fileSystemProvider API to create file systems, that can be accessible from the file manager on Chrome OS. Use the clarativeContent API to take actions depending on the content of a page, without requiring permission to read the page's content. Use the Debuggee tabId to target tabs with sendCommand and route events by tabId from onEvent callbacks. Use bugger to attach to one or more tabs to instrument network interaction, debug JavaScript, mutate the DOM and CSS, etc. The bugger API serves as an alternate transport for Chrome's remote debugging protocol. Use the okies API to query and modify cookies, and to be notified when they change. You can choose what types of objects your context menu additions apply to, such as images, hyperlinks, and pages. Use the ntextMenus API to add items to Google Chrome's context menu. More generally speaking, content settings allow you to customize Chrome's behavior on a per-site basis instead of globally. Use the ntentSettings API to change settings that control whether websites can use features such as cookies, JavaScript, and plugins. Use the commands API to add keyboard shortcuts that trigger actions in your extension, for example, an action to open the browser action or send a command to the extension. Use this API to expose certificates to the platform which can use these certificates for TLS authentications. Note that accessibilityFeatures.modify does not imply accessibilityFeatures.read permission. For modifying feature state, the extension needs accessibilityFeatures.modify permission. In order to get feature states the extension must request accessibilityFeatures.read permission. This API relies on the ChromeSetting prototype of the type API for getting and setting individual accessibility features. Use the chrome.accessibilityFeatures API to manage Chrome's accessibility features. Release information is not available for APIs before Chrome 42, which was released in early 2015.

If you need to know the outcome of an operation, then you pass a callback function into the method.

Unless the doc says otherwise, methods in the chrome.* APIs are asynchronous: they return immediately, without waiting for the operation to finish. Chrome provides extensions with many special-purpose APIs like ntime and chrome.alarms.

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