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InboxSDK

Build apps inside Gmail

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InboxSDK is a high-level JavaScript library for building browser extensions that run inside Gmail. It abstracts Gmail's DOM so developers work with classes and methods, such as ComposeView, instead of locating selectors or tracking Gmail's interface changes. The library is remote loaded and updated to keep pace with Gmail.

Capabilities include adding buttons to compose and reply windows, toolbars, and navigation; labeling emails with tags, images, or buttons; adding sidebar content; parsing email messages and displaying attachment cards; inserting results into search autocomplete; adding full-screen content and sections above the inbox; and registering keyboard shortcuts. It provides consistent UI elements including buttons, dropdowns, lists, text fields, checkboxes, and modals, and handles configurations such as multiple inboxes, preview panes, compose modes, themes, and Gmail Labs.

It is aimed at developers building browser extensions for Gmail, including internal tools deployed to a company's own domain or organization. Documentation is available, and the library is hosted on GitHub.

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