webextensions-examples/embedded-webextension-bootstrapped/README.md

This is a very simple example of how to use a WebExtension embedded in a Legacy Add-on to be able to gradually port a legacy addon written as a Bootstrapped extension into a pure WebExtension and migrate the legacy addon data into the WebExtensions storage.local.

The simple example legacy addon provides:

• a button in the toolbar
• some user data stored in the Firefox preferences
• when the button is pressed, it shows a panel which renders the above data from the Firefox preferences

The transition example is composed of 3 steps:

• Step 0: original legacy addon, everything is written using the legacy Addon implementation strategies
• Step 1: hybrid addon (a Boostrapped legacy container addon with a simple webextension embedded into it), the legacy code provides access to the preferences and handle (with the background page) the transition of this data into the WebExtensions storage.local StorageArea, the webextension provides the UI and the new data storage.
• Step 2: a pure WebExtensions addon is extracted from the Step 1 (once the old users have been already able to transition their data using the step 1 version)