Uncaught TypeError: Cannot read property 'local' of undefined in chrome extension
Make sure that all necessary permissions have been declared in the manifest file. "storage", in your case.
In general, the following steps should fix the problem of apparently undefined Chrome APIs:
- Read the documentation of the API you're using and get yourself familiar with the prerequisites, usually manifest permissions (e.g.
chrome.storage#manifest). - Check if your (user's) Chrome version supports the API, by looking at What's new.
- Check if the script is running in the right context. Most APIs are only available to the extension's process. (the
chrome.storageAPI can also be used in content script though) - Otherwise, resort to your usual debugging skills: Typos, variable shadowing, ...